1
|
McGinnis CB, Wang F, Chiappelli AL, Okonkwo DO, Darby JM. Phenobarbital as Anticonvulsant Prophylaxis in Patients With Traumatic Brain Injury at Risk for Alcohol Withdrawal Syndrome. J Pharm Pract 2024; 37:665-670. [PMID: 36961745 DOI: 10.1177/08971900231167932] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/25/2023]
Abstract
Background: Anticonvulsant prophylaxis (ACP) for early post-traumatic seizures (PTS) is recommended in patients with traumatic brain injury (TBI). Phenobarbital (PB) may be used to prevent alcohol withdrawal syndrome (AWS) in at-risk patients. The dual-purpose use of PB in the TBI population would allow for consolidation of pharmacotherapy. Objective: The primary objective of this study was to determine the frequency of early PTS in TBI patients at risk of AWS treated with PB as ACP. Secondary objectives included determining rates of over sedation and endotracheal intubation. Methods: Patients received an intravenous (IV) loading dose of PB at 15-20 mg/kg followed by 1 mg/kg every 12 hours for 7 days with a goal level of 15-20 mcg/mL. Medication data, seizure frequency, and episodes of over sedation and endotracheal intubation were collected. Results: Eighty patients were treated with PB over a 1-year period. Thirty-nine patients were analyzed. Median loading dose was 19.9 (Interquartile Range 19.1-20.0) mg/kg with a median post load level of 21.7 mcg/mL (IQR 18.3-25.8) mcg/mL. One patient (2.6%) had electrographic evidence for early PTS. PB was discontinued in 4 (10.3%) patients out of concern for over sedation. One patient required endotracheal intubation after rapid PB loading. Conclusion: The frequency of early PTS was low when PB was used as primary ACP in patients with TBI at risk for AWS. Over sedation is a potential adverse effect that should be considered in the choice of ACP. No conclusions can be drawn as to the effectiveness of PB in preventing AWS.
Collapse
Affiliation(s)
- Cory B McGinnis
- Department of Pharmacy, UPMC Presbyterian, Pittsburgh, PA, USA
| | - Fajun Wang
- Department of Critical Care Medicine, The University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | | | - David O Okonkwo
- Department of Neurological Surgery, The University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Joseph M Darby
- Department of Critical Care Medicine, The University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
- Department of Neurological Surgery, The University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
- Department of Surgery, The University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| |
Collapse
|
2
|
De Sutter PJ, Rossignol P, Breëns L, Gasthuys E, Vermeulen A. Predicting Volume of Distribution in Neonates: Performance of Physiologically Based Pharmacokinetic Modelling. Pharmaceutics 2023; 15:2348. [PMID: 37765316 PMCID: PMC10536587 DOI: 10.3390/pharmaceutics15092348] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2023] [Revised: 09/12/2023] [Accepted: 09/17/2023] [Indexed: 09/29/2023] Open
Abstract
The volume of distribution at steady state (Vss) in neonates is still often estimated through isometric scaling from adult values, disregarding developmental changes beyond body weight. This study aimed to compare the accuracy of two physiologically based pharmacokinetic (PBPK) Vss prediction methods in neonates (Poulin & Theil with Berezhkovskiy correction (P&T+) and Rodgers & Rowland (R&R)) with isometrical scaling. PBPK models were developed for 24 drugs using in-vitro and in-silico data. Simulations were done in Simcyp (V22) using predefined populations. Clinical data from 86 studies in neonates (including preterms) were used for comparison, and accuracy was assessed using (absolute) average fold errors ((A)AFEs). Isometric scaling resulted in underestimated Vss values in neonates (AFE: 0.61), and both PBPK methods reduced the magnitude of underprediction (AFE: 0.82-0.83). The P&T+ method demonstrated superior overall accuracy compared to isometric scaling (AAFE of 1.68 and 1.77, respectively), while the R&R method exhibited lower overall accuracy (AAFE: 2.03). Drug characteristics (LogP and ionization type) and inclusion of preterm neonates did not significantly impact the magnitude of error associated with isometric scaling or PBPK modeling. These results highlight both the limitations and the applicability of PBPK methods for the prediction of Vss in the absence of clinical data.
Collapse
|
3
|
Alwakeel M, Alayan D, Saleem T, Afzal S, Immler E, Wang X, Akbik B, Duggal A. Phenobarbital-Based Protocol for Alcohol Withdrawal Syndrome in a Medical ICU: Pre-Post Implementation Study. Crit Care Explor 2023; 5:e0898. [PMID: 37091477 PMCID: PMC10115550 DOI: 10.1097/cce.0000000000000898] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/25/2023] Open
Abstract
We assessed the efficacy and safety of PB compared with benzodiazepine (BZD)-based protocols in treating AWS in MICU. DESIGN Single-center, pre-post protocol implementation study. SETTING The setting is a forty-bed MICU in a tertiary-level academic medical center. PATIENTS We included all patients admitted to the MICU with a primary diagnosis of AWS. INTERVENTIONS Intravenous PB 260 mg followed by 130-mg doses every 15-30 minutes as needed up to 15 mg/kg of ideal body weight versus escalating doses of BZD, to achieve a Clinical Institute Withdrawal Assessment Alcohol Scale-Revised score less than 10. MEASUREMENTS AND MAIN RESULTS ICU and hospital length of stay (LOS), in addition to safety measures were the main outcomes of the study. A total of 102 patients were included, 51 in the PB arm and 51 in the BZD arm. There were no differences in baseline clinical characteristics. Half the patients in each group were admitted with delirium tremens. The use of PB-based protocol was associated with 35% reduction in median ICU LOS (1.5 d [interquartile range, 1.2-2.4 d] vs 2.3 d [1.4-4.8 d]; p = 0.009) and 50% reduction in hospital LOS (3 d [2.7-4 d] vs 6 d [4-10 d]; p < 0.001). After adjustment for comorbidities and clinical factors, PB protocol decreased ICU LOS days by 40% (95% CI; 25.8-53.5%). PB group required fewer adjunctive medications to control symptoms (0.7 [0.5-1] vs 2.5 [2-3]; p < 0.001), less need for intubation (1/51 [2%] vs 10/10 [19.6%]; p = 0.023) and less need for physical restraint (19/51 [37.3%] vs 29/51 [56.9%]; p = 0.047), compared with the BZD group. CONCLUSIONS A protocol utilizing rapidly escalating doses of PB over a short period is an effective and safe alternative to BZD in treating AWS in MICU.
Collapse
Affiliation(s)
- Mahmoud Alwakeel
- Department of Pulmonary & Critical Care Medicine, Respiratory Institute, Cleveland Clinic, Cleveland, OH
| | - Dina Alayan
- Department of Internal Medicine, Cleveland Clinic Fairview Hospital, Cleveland, OH
| | - Talha Saleem
- Department of Pulmonary & Critical Care Medicine, Respiratory Institute, Cleveland Clinic, Cleveland, OH
| | - Saira Afzal
- Neurology Department, Cleveland Clinic Florida, Weston, FL
| | - Ellen Immler
- Department of Pharmacy, Cleveland Clinic Fairview Hospital, Cleveland, OH
| | - Xiaofeng Wang
- Qualitative Health Sciences, Cleveland Clinic, Cleveland, OH
| | - Bassel Akbik
- Critical Care Department, Houston Methodist, Houston, TX
| | - Abhijit Duggal
- Department of Pulmonary & Critical Care Medicine, Respiratory Institute, Cleveland Clinic, Cleveland, OH
| |
Collapse
|
4
|
Trinka E. Phenobarbital in Status epilepticus - Rediscovery of an effective drug. Epilepsy Behav 2023; 141:109104. [PMID: 36807987 DOI: 10.1016/j.yebeh.2023.109104] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/07/2023] [Accepted: 01/19/2023] [Indexed: 02/22/2023]
Abstract
Phenobarbital (PB) is one of the oldest Antiseizure Medicines (ASMs), which is in clinical use since 1912. Its value in the treatment of Status epilepticus is currently discussed controversially. Phenobarbital has fallen out of favor in many countries across Europe because of reports of hypotension, arrhythmias, and hypopnea. Phenobarbital has a strong antiseizure effect with remarkably little sedation. It exerts its clinical effects, through the increase of GABE-ergic inhibition and decrease of glutamatergic excitation by inhibition of AMPA receptors. Despite good preclinical evidence, there are remarkably few randomized controlled studies on humans in SE, which suggest, that it is at least as good as lorazepam in first-line treatment in early SE, and significantly better than valproic acid in benzodiazepine-resistant SE. Data from randomized trials and large non-randomized prospective and retrospective studies suggest, that Phenobarbital is well tolerated even if used in very high dose protocols. Thus, despite its decline in its popularity at least in Europe and North America, it should be considered a highly cost-effective treatment for early and established SE, not only in resource-limited settings. This paper was presented at the 8th London-Innsbruck Colloquium on Status Epilepticus and Acute Seizures held in September 2022.
Collapse
Affiliation(s)
- Eugen Trinka
- Department of Neurology, Christian-Doppler University Hospital, Paracelsus Medical University, Centre for Cognitive Neuroscience, Member of EpiCARE, Salzburg, Austria; Neuroscience Institute, Christian-Doppler University Hospital, Paracelsus Medical University, Centre for Cognitive Neuroscience, Salzburg, Austria; Institute of Public Health, Medical Decision-Making and HTA, UMIT - Private University for Health Sciences, Medical Informatics and Technology, Hall in Tyrol, Austria.
| |
Collapse
|
5
|
Mechanical Ventilation in Patients with Traumatic Brain Injury: Is it so Different? Neurocrit Care 2023; 38:178-191. [PMID: 36071333 DOI: 10.1007/s12028-022-01593-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2022] [Accepted: 08/16/2022] [Indexed: 10/14/2022]
Abstract
Patients with traumatic brain injury (TBI) frequently require invasive mechanical ventilation and admission to an intensive care unit. Ventilation of patients with TBI poses unique clinical challenges, and careful attention is required to ensure that the ventilatory strategy (including selection of appropriate tidal volume, plateau pressure, and positive end-expiratory pressure) does not cause significant additional injury to the brain and lungs. Selection of ventilatory targets may be guided by principles of lung protection but with careful attention to relevant intracranial effects. In patients with TBI and concomitant acute respiratory distress syndrome (ARDS), adjunctive strategies include sedation optimization, neuromuscular blockade, recruitment maneuvers, prone positioning, and extracorporeal life support. However, these approaches have been largely extrapolated from studies in patients with ARDS and without brain injury, with limited data in patients with TBI. This narrative review will summarize the existing evidence for mechanical ventilation in patients with TBI. Relevant literature in patients with ARDS will be summarized, and where available, direct data in the TBI population will be reviewed. Next, practical strategies to optimize the delivery of mechanical ventilation and determine readiness for extubation will be reviewed. Finally, future directions for research in this evolving clinical domain will be presented, with considerations for the design of studies to address relevant knowledge gaps.
Collapse
|
6
|
Mukhtar I, Anwar H, Iftikhar A, Hashem HE, Ali Q, Siddique F. Human targeted phenobarbital presents a poor substrate of gut microbiome deciphering new drug targets beyond pharmacokinetic curbs. BMC Pharmacol Toxicol 2022; 23:85. [DOI: 10.1186/s40360-022-00618-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2022] [Accepted: 09/27/2022] [Indexed: 11/15/2022] Open
Abstract
Abstract
Background
The gut microbiome, a new organ of the body, can potentially alter the pharmacokinetics of orally administered drugs through microbial enzymes. However, absorption of orally administered non-antibiotic drugs by the gut microbiome, during drug-microbiome interaction, is barely addressed. Structural homology studies confirm similar membrane transport proteins in gut epithelial cells and the gut microbiome of the host that may compete for drug substrates with the host itself for its absorbance. Therefore, it is hypothesized that orally administered human targeted phenobarbital may interact and/or be uptake by the gut microbiome during its transit through the small intestine.
Methods
In the current in vivo study, thirty-six male Wistar albino rats were divided into six groups including one control and 5 treatment groups, each having an equal number of rats (n = 6). Phenobarbital was administered orally (single dose of 15 mg/kg bw) to treatment groups. Animals were subsequently sacrificed to harvest microbial mass pallets residing in the small intestine after 2, 3, 4, 5, and 6 h of phenobarbital administration. Phenobarbital absorbance by the microbiome in the microbial lysate was estimated through RP-HPLC–UV at a wavelength of 207 nm.
Results
Maximum phenobarbital absorbance (149.0 ± 5.93 µg) and drug absorbance per milligram of microbial mass (1.19 ± 0.05 µg) were found significantly higher at 4 h of post-administration in comparison to other groups. Percent dose recovery of phenobarbital was 5.73 ± 0.19% at 4 h while the maximum intestinal transit time was 5 h till the drug was absorbed by the microbes. Such results pronounce the idea of the existence of structural homology between membrane transporters of the gut microbiome and intestinal enterocytes of the host that may competitively absorb orally administered phenobarbital during transit in the small intestine. The docking studies revealed that the phenobarbital is a poor substrate for the gut microbiome.
Conclusion
Gut microbiome may competitively absorb the non-antibiotics such as phenobarbital as novel substrates due to the presence of structurally homologous transporting proteins as in enterocytes. This phenomenon suggests the microbiome as a potential candidate that can significantly alter the pharmacokinetics of drugs.
Collapse
|
7
|
Ma CD, Van Horn CG, Wan M, Bishop C, Bonkovsky HL. Assessment of porphyrogenicity of drugs and chemicals in selected hepatic cell culture models through a fluorescence-based screening assay. Pharmacol Res Perspect 2022; 10:e00951. [PMID: 35445802 PMCID: PMC9022196 DOI: 10.1002/prp2.951] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/25/2021] [Accepted: 04/02/2022] [Indexed: 12/15/2022] Open
Abstract
Compounds that induce 5-aminolevulinic acid [ALA] synthase-1 and/or cytochromes P-450 may induce acute porphyric attacks in patients with the acute hepatic porphyrias [AHPs]. Currently, there is no simple, robust model used to assess and predict the porphyrogenicity of drugs and chemicals. Our aim was to develop a fluorescence-based in vitro assay for this purpose. We studied four different hepatic cell culture models: HepG2 cells, LMH cells, 3D HepG2 organoids, and 3D organoids of primary liver cells from people without known disease [normal human controls]. We took advantage of the fluorescent properties of protoporphyrin IX [PP], the last intermediate of the heme biosynthesis pathway, performing fluorescence spectrometry to measure the intensity of fluorescence emitted by these cells treated with selected compounds of importance to patients with AHPs. Among the four cell culture models, the LMH cells produced the highest fluorescence readings, suggesting that these cells retain more robust heme biosynthesis enzymes or that the other cell models may have lost their inducibility of ALA synthase-1 [ALAS-1]. Allyl isopropyl acetamide [AIA], a known potent porphyrogen and inducer of ALAS-1, was used as a positive control to help predict porphyrogenicity for tested compounds. Among the tested compounds (acetaminophen, acetylsalicylic acid, β-estradiol, hydroxychloroquine sulfate, alpha-methyldopa, D (-) norgestrel, phenobarbital, phenytoin, sulfamethoxazole, sulfisoxazole, sodium valproate, and valsartan), concentrations greater than 0.314 mM for norgestrel, phenobarbital, phenytoin, and sodium valproate produced fluorescence readings higher than the reading produced by the positive AIA control. Porphyrin accumulation was also measured by HPLC to confirm the validity of the assay. We conclude that LMH cell cultures in multi-well plates are an inexpensive, robust, and simple system to predict the porphyrogenicity of existing or novel compounds that may exacerbate the AHPs.
Collapse
Affiliation(s)
- Christopher D Ma
- Department of Internal Medicine, Section on Gastroenterology and Hepatology, Wake Forest University School of Medicine, Winston-Salem, North Carolina, USA
| | - Cynthia G Van Horn
- Department of Internal Medicine, Section on Gastroenterology and Hepatology, Wake Forest University School of Medicine, Winston-Salem, North Carolina, USA
| | - Meimei Wan
- Wake Forest Institute for Regenerative Medicine, Wake Forest University, Winston-Salem, North Carolina, USA
| | - Colin Bishop
- Wake Forest Institute for Regenerative Medicine, Wake Forest University, Winston-Salem, North Carolina, USA
| | - Herbert L Bonkovsky
- Department of Internal Medicine, Section on Gastroenterology and Hepatology, Wake Forest University School of Medicine, Winston-Salem, North Carolina, USA
| |
Collapse
|
8
|
In Silico Prediction of Pharmacokinetic Profile for Human Oral Drug Candidates Which Lack Clinical Pharmacokinetic Experiment Data. Eur J Drug Metab Pharmacokinet 2022; 47:403-417. [PMID: 35171461 DOI: 10.1007/s13318-022-00758-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/25/2022] [Indexed: 11/03/2022]
Abstract
BACKGROUNDS AND OBJECTIVES In silico methods which can generate high-quality physiologically based pharmacokinetic (PBPK) models for arbitrary drug candidates are greatly needed to select developable drug candidates that escape drug attrition because of the poor pharmacokinetic profile. The purpose of this study is to develop a novel protocol to preliminarily predict the concentration profile of a target drug based on the PBPK model of a structurally similar template drug by combining two software platforms for PBPK modeling, the SimCYP simulator and ADMET Predictor. METHODS The method was evaluated by utilizing 13 drug pairs from 18 drugs in the built-in database of the SimCYP software. All drug pairs have Tanimoto scores (TS) no less than 0.5. As each drug in a drug pair can serve as both target and template, 26 sets were studied in this work. Three versions (V1, V2 and V3) of models for the target drug were constructed by replacing the corresponding parameters of the template drug step by step with those predicted by ADMET Predictor for the target drug. V1 represents the replacement of molecular weight (MW), V2 includes the replacement of parameter MW, fraction unbound in plasma (fu), blood-to-plasma partition ratio (B/P), logarithm of the octanol-buffer partition coefficient (log Po:w) and acid dissociation constant (pKa). In V3, all above-mentioned parameters as well as human jejunum effective permeability (Peff), Vd and cytochrome P450 (CYP) metabolism parameters (Km, Vmax or CLint) are modified. Normalized root mean square error (NRMSE) was used for the evaluation of the model performance. RESULTS We found that the performance of the three versions of the models depends on structural similarity of the drug pairs. For Group I drug pairs (TS ≤ 0.7), V2 and V3 performed better than V1 in terms of NRMSE; for Group II drug pairs (0.7 < TS ≤ 0.9), 8 out of 10 V3 models had NRMSE < 0.2, the cutoff we applied to judge whether the simulated concentration-time (C-T) curve was satisfactory or not. V3 outperformed the V1 and V2 versions. For the two drug pairs belonging to Group III (TS > 0.9), V2 outperformed V1 and V3, suggesting more unnecessary replacement can lower the performance of PBPK models. We also investigated how the prediction accuracy of ADMET Predictor as well as its collaboration with SimCYP influences the quality of PBPK models constructed using SimCYP. CONCLUSION In conclusion, we generated practical guidance on applying two mainstream software packages, ADMET Predictor and SimCYP, to construct PBPK models for drugs or drug candidates that lack ADME parameters in model construction.
Collapse
|
9
|
Sae-Heng T, Rajoli RKR, Siccardi M, Karbwang J, Na-Bangchang K. Physiologically based pharmacokinetic modeling for dose optimization of quinine-phenobarbital coadministration in patients with cerebral malaria. CPT-PHARMACOMETRICS & SYSTEMS PHARMACOLOGY 2021; 11:104-115. [PMID: 34730282 PMCID: PMC8752110 DOI: 10.1002/psp4.12737] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/17/2021] [Revised: 10/04/2021] [Accepted: 10/12/2021] [Indexed: 11/22/2022]
Abstract
Patients with cerebral malaria with polymorphic Cytochrome P450 2C19 (CYP2C19) genotypes who receive concurrent treatment with quinine are at risk of inadequate or toxic therapeutic drug concentrations due to metabolic drug interactions. The study aimed to predict the potential dose regimens of quinine when coadministered with phenobarbital in adult patients with cerebral malaria and complications (e.g., lactic acidosis and acute renal failure) and concurrent with seizures and acute renal failure who carry wild‐type and polymorphic CYP2C19. The whole‐body physiologically based pharmacokinetic (PBPK) models for quinine, phenobarbital, and quinine–phenobarbital coadministration were constructed based on the previously published information using Simbiology®. Four published articles were used for model validation. A total of 100 virtual patients were simulated based on the 14‐day and 3‐day courses of treatment. using the drug–drug interaction approach. The predicted results were within 15% of the observed values. Standard phenobarbital dose, when administered with quinine, is suitable for all groups with single or continuous seizures regardless of CYP2C19 genotype, renal failure, and lactic acidosis. Dose adjustment based on area under the curve ratio provided inappropriate quinine concentrations. The recommended dose of quinine when coadministered with phenobarbital based on the PBPK model for all groups is a loading dose of 2000 mg intravenous (i.v.) infusion rate 250 mg/h followed by 1200 mg i.v. rate 150 mg/h. The developed PBPK models are credible for further simulations. Because the predicted quinine doses in all groups were similar regardless of the CYP2C19 genotype, genotyping may not be required.
Collapse
Affiliation(s)
- Teerachat Sae-Heng
- Center of Excellence in Pharmacology and Molecular Biology of Malaria and Cholangiocarcinoma, Chulabhorn International College, Thammasat University (Rangsit Campus), Pathumthani, Thailand
| | | | - Marco Siccardi
- Department of Molecular and Clinical Pharmacology, University of Liverpool, Liverpool, UK
| | - Juntra Karbwang
- Center of Excellence in Pharmacology and Molecular Biology of Malaria and Cholangiocarcinoma, Chulabhorn International College, Thammasat University (Rangsit Campus), Pathumthani, Thailand.,Drug Discovery and Development Center, Office of Advanced Science and Technology, Thammasat University (Rangsit Campus), Pathumthani, Thailand
| | - Kesara Na-Bangchang
- Center of Excellence in Pharmacology and Molecular Biology of Malaria and Cholangiocarcinoma, Chulabhorn International College, Thammasat University (Rangsit Campus), Pathumthani, Thailand.,Drug Discovery and Development Center, Office of Advanced Science and Technology, Thammasat University (Rangsit Campus), Pathumthani, Thailand
| |
Collapse
|
10
|
Doyno CR, White CM. Sedative-Hypnotic Agents That Impact Gamma-Aminobutyric Acid Receptors: Focus on Flunitrazepam, Gamma-Hydroxybutyric Acid, Phenibut, and Selank. J Clin Pharmacol 2021; 61 Suppl 2:S114-S128. [PMID: 34396551 DOI: 10.1002/jcph.1922] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2021] [Accepted: 06/03/2021] [Indexed: 12/29/2022]
Abstract
There are many nonopioid central nervous system depressant substances that share a gamma-aminobutyric acid (GABA) receptor-related mechanism of action. These sedatives-hypnotics can be indicated to treat anxiety, seizures, depression, and insomnia but are also used as substances of abuse and used to facilitate sexual assault. Barbiturates, methaqualone, and glutethimide were among the first type A GABA receptor-mediated sedative-hypnotics. Their clinical use was limited for most indications by serious adverse events and strong abuse potential but continue to be used illicitly around the world. The benzodiazepines supplanted barbiturates for most indications because they were less likely to cause severe adverse events in monotherapy. Flunitrazepam is a newer benzodiazepine that is preferentially used recreationally and to facilitate sexual assault. Flunitrazepam has greater potency and higher affinity for the type A GABA receptor than most benzodiazepines. Gamma-hydroxybutyric acid is sought illicitly for its hypnotic, euphoric and anabolic effects as well as to facilitate sexual assault. When any of these GABAergic drugs are used in high doses or with other sedative hypnotic agents, respiratory depression, coma, and death have occurred. Chronic use of these GABAergic drugs can lead to significant withdrawal syndromes. Phenibut and selank are poorly studied Russian drugs with GABAergic mechanisms that are inexplicably sold to US consumers as dietary supplements. Poison control center calls regarding phenibut have increased substantially over the past 5 years. Desired euphoriant effects account for the recreational and illicit use of many GABA-modulating agents. However, illicit use can lead to significant toxicities related to abuse, dependence, and subsequent withdrawal syndromes. Significant evaluation of developing agents with GABA properties should be conducted to determine abuse potential before public access ensues.
Collapse
Affiliation(s)
- Cassandra R Doyno
- Department of Pharmacy Practice, University of Connecticut School of Pharmacy, Storrs, Connecticut, USA.,John Dempsey Hospital, University of Connecticut, Farmington, Connecticut, USA
| | - C Michael White
- Department of Research Administration, Hartford Hospital, Hartford, Connecticut, USA
| |
Collapse
|
11
|
Mastroianni G, Iannone LF, Roberti R, Gasparini S, Ascoli M, Cianci V, De Sarro G, Gambardella A, Labate A, Brigo F, Russo E, Aguglia U, Ferlazzo E. Management of status epilepticus in patients with liver or kidney disease: a narrative review. Expert Rev Neurother 2020; 21:1251-1264. [PMID: 33297776 DOI: 10.1080/14737175.2021.1862649] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Introduction: Status epilepticus (SE) is a neurologic and medical emergency with significant related morbidity and mortality. Hepatic or renal dysfunction can considerably affect the pharmacokinetics of drugs used for SE through a variety of direct or indirect mechanisms.Areas Covered: This review aims to focus on the therapeutic management of SE in patients with hepatic or renal impairment, highlighting drugs' selection and dose changes that may be necessary due to altered drug metabolism and excretion. The references for this review were identified by searches of PubMed and Google Scholar until May 2020.Expert opinion: According to literature evidence and clinical experience, in patients with renal disease, the authors suggest considering lorazepam as the drug of choice in pre-hospital and intra-hospital early-stage SE, phenytoin in definite SE, propofol in refractory or super-refractory SE. In patients with liver disease, the authors suggest the use of lorazepam as drug of choice in pre-hospital and intra-hospital early-stage SE, lacosamide in definite SE, propofol in refractory or super-refractory SE. A list of preferred drugs for all SE stages is provided.
Collapse
Affiliation(s)
- Giovanni Mastroianni
- Regional Epilepsy Centre, Great Metropolitan "Bianchi-Melacrino-Morelli" Hospital, Reggio, Italy
| | | | - Roberta Roberti
- Science of Health Department, School of Medicine, Magna Græcia University, Catanzaro, Italy
| | - Sara Gasparini
- Regional Epilepsy Centre, Great Metropolitan "Bianchi-Melacrino-Morelli" Hospital, Reggio, Italy.,Department of Medical and Surgical Sciences, Magna Græcia University, Catanzaro, Italy
| | - Michele Ascoli
- Regional Epilepsy Centre, Great Metropolitan "Bianchi-Melacrino-Morelli" Hospital, Reggio, Italy.,Department of Medical and Surgical Sciences, Magna Græcia University, Catanzaro, Italy
| | - Vittoria Cianci
- Regional Epilepsy Centre, Great Metropolitan "Bianchi-Melacrino-Morelli" Hospital, Reggio, Italy
| | | | - Antonio Gambardella
- Department of Medical and Surgical Sciences, Magna Græcia University, Catanzaro, Italy.,Institute of Molecular Bioimaging and Physiology, National Research Council, Catanzaro, Italy
| | - Angelo Labate
- Department of Medical and Surgical Sciences, Magna Græcia University, Catanzaro, Italy.,Institute of Molecular Bioimaging and Physiology, National Research Council, Catanzaro, Italy
| | - Francesco Brigo
- Department of Neurology, Franz Tappeiner Hospital, Merano, Italy
| | - Emilio Russo
- Science of Health Department, School of Medicine, Magna Græcia University, Catanzaro, Italy
| | - Umberto Aguglia
- Regional Epilepsy Centre, Great Metropolitan "Bianchi-Melacrino-Morelli" Hospital, Reggio, Italy.,Department of Medical and Surgical Sciences, Magna Græcia University, Catanzaro, Italy.,Institute of Molecular Bioimaging and Physiology, National Research Council, Catanzaro, Italy
| | - Edoardo Ferlazzo
- Regional Epilepsy Centre, Great Metropolitan "Bianchi-Melacrino-Morelli" Hospital, Reggio, Italy.,Department of Medical and Surgical Sciences, Magna Græcia University, Catanzaro, Italy.,Institute of Molecular Bioimaging and Physiology, National Research Council, Catanzaro, Italy
| |
Collapse
|
12
|
van Hoogdalem MW, McPhail BT, Hahn D, Wexelblatt SL, Akinbi HT, Vinks AA, Mizuno T. Pharmacotherapy of neonatal opioid withdrawal syndrome: a review of pharmacokinetics and pharmacodynamics. Expert Opin Drug Metab Toxicol 2020; 17:87-103. [PMID: 33049155 DOI: 10.1080/17425255.2021.1837112] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
INTRODUCTION Neonatal opioid withdrawal syndrome (NOWS) often arises in infants born to mothers who used opioids during pregnancy. Morphine, methadone, and buprenorphine are the most common first-line treatments, whereas clonidine and phenobarbital are generally reserved for adjunctive therapy. These drugs exhibit substantial pharmacokinetic (PK) and pharmacodynamic (PD) variability. Current pharmacological treatments for NOWS are based on institutional protocols and largely rely on empirical treatment of patient symptoms. AREAS COVERED This article reviews the PK/PD of NOWS pharmacotherapies with a focus on the implication of physiological development and maturation. Body size-standardized clearance is consistently low in neonates, except for methadone. This can be ascribed to underdeveloped metabolic and elimination pathways. The effects of pharmacogenetics have been clarified especially for morphine. The PK/PD relationship of medications used in the treatment of NOWS is generally understudied. EXPERT OPINION Providing an appropriate opioid dose in neonates is challenging. Advancements in quantitative pharmacology and PK/PD modeling approaches facilitate identification of key factors driving PK/PD variability and characterization of exposure-response relationships. PK/PD model-informed simulations have been widely employed to define age-appropriate pediatric dosing regimens. The model-informed approach holds promise to aid more rational use of medications in the treatment of NOWS.
Collapse
Affiliation(s)
- Matthijs W van Hoogdalem
- Division of Clinical Pharmacology, Cincinnati Children's Hospital Medical Center , Cincinnati, OH, USA.,James L. Winkle College of Pharmacy, University of Cincinnati , Cincinnati, OH, USA
| | - Brooks T McPhail
- Division of Clinical Pharmacology, Cincinnati Children's Hospital Medical Center , Cincinnati, OH, USA.,School of Medicine Greenville, University of South Carolina , Greenville, SC, USA
| | - David Hahn
- Division of Clinical Pharmacology, Cincinnati Children's Hospital Medical Center , Cincinnati, OH, USA
| | - Scott L Wexelblatt
- Perinatal Institute, Division of Neonatology, Cincinnati Children's Hospital Medical Center , Cincinnati, OH, USA.,Department of Pediatrics, College of Medicine, University of Cincinnati , Cincinnati, OH, USA.,Center for Addiction Research, College of Medicine, University of Cincinnati , Cincinnati, OH, USA
| | - Henry T Akinbi
- Perinatal Institute, Division of Neonatology, Cincinnati Children's Hospital Medical Center , Cincinnati, OH, USA.,Department of Pediatrics, College of Medicine, University of Cincinnati , Cincinnati, OH, USA
| | - Alexander A Vinks
- Division of Clinical Pharmacology, Cincinnati Children's Hospital Medical Center , Cincinnati, OH, USA.,Department of Pediatrics, College of Medicine, University of Cincinnati , Cincinnati, OH, USA.,Center for Addiction Research, College of Medicine, University of Cincinnati , Cincinnati, OH, USA
| | - Tomoyuki Mizuno
- Division of Clinical Pharmacology, Cincinnati Children's Hospital Medical Center , Cincinnati, OH, USA.,Department of Pediatrics, College of Medicine, University of Cincinnati , Cincinnati, OH, USA.,Center for Addiction Research, College of Medicine, University of Cincinnati , Cincinnati, OH, USA
| |
Collapse
|
13
|
Teixeira-da-Silva P, Santos-Buelga D, Otero MJ, García MJ. Population pharmacokinetics of phenobarbital in Caucasian patients with epilepsy. Eur J Pharm Sci 2020; 153:105484. [PMID: 32707172 DOI: 10.1016/j.ejps.2020.105484] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2019] [Revised: 06/16/2020] [Accepted: 07/20/2020] [Indexed: 11/30/2022]
Abstract
The present study aimed to establish a population pharmacokinetic (PopPK) model of Phenobarbital (PB) in Caucasian patients with epilepsy included in a Therapeutic Drug Monitoring program. In total, 855 PB serum concentrations (steady-state trough concentrations) were retrospectively collected during routine clinical monitoring of 395 patients over 15 years of age with epilepsy. The PopPK analysis was performed with NONMEM using a non-linear mixed-effect modelling approach. The influence of demographic, anthropometric, treatment, and comedication variables on the apparent clearance (CL/F) of PB were analysed. Goodness of fit plots and the bootstrap method were performed to evaluate the final model. External validation was carried out using an independent group of patients (107 patients, 178 blood samples). A one-compartment model with first-order absorption and elimination successfully described the data. In the final model, CL/F included body surface area (BSA) and comedication with phenytoin (PHT) and valproic acid (VPA), resulting in the following equation: CL/F[L/h]=(0.236+(0.115×(BSA-1.7)))×(0.822PHT)×(0.711VPA) The model presents acceptable estimation errors in the parameters of fixed (<12%) and random effects (<13%), and of the shrinkage values (<21%). Internal and external validations demonstrated the good predictability of the final model. A PopPK model of PB in Caucasian patients over 15 years of age was successfully established, which can be used to estimate phenobarbital CL/F. BSA and drug-drug interactions with PHT and VPA should be incorporated into dosing decisions. This PopPK, using Bayesian algorithms, could help establish an optimal dosage regimen in routine patient care.
Collapse
Affiliation(s)
- Paulo Teixeira-da-Silva
- Department of Pharmaceutical Sciences, Pharmacy and Pharmaceutical Technology Section, Faculty of Pharmacy, Universidad de Salamanca, Campus Miguel de Unamuno, Calle Lic. Méndez Nieto, s/n, Salamanca, Spain.
| | - Dolores Santos-Buelga
- Department of Pharmaceutical Sciences, Pharmacy and Pharmaceutical Technology Section, Faculty of Pharmacy, Universidad de Salamanca, Campus Miguel de Unamuno, Calle Lic. Méndez Nieto, s/n, Salamanca, Spain
| | - María José Otero
- Department of Pharmaceutical Sciences, Pharmacy and Pharmaceutical Technology Section, Faculty of Pharmacy, Universidad de Salamanca, Campus Miguel de Unamuno, Calle Lic. Méndez Nieto, s/n, Salamanca, Spain; Pharmacy Service, University Hospital of Salamanca, Paseo de San Vicente, 182, Salamanca, Spain
| | - María José García
- Department of Pharmaceutical Sciences, Pharmacy and Pharmaceutical Technology Section, Faculty of Pharmacy, Universidad de Salamanca, Campus Miguel de Unamuno, Calle Lic. Méndez Nieto, s/n, Salamanca, Spain
| |
Collapse
|
14
|
Verstegen RHJ, Anderson PO, Ito S. Infant drug exposure via breast milk. Br J Clin Pharmacol 2020; 88:4311-4327. [PMID: 32860456 DOI: 10.1111/bcp.14538] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2020] [Revised: 08/08/2020] [Accepted: 08/26/2020] [Indexed: 12/31/2022] Open
Abstract
More than half of women take medications during breastfeeding, predisposing their infants to medication exposure via breast milk. As a result, adverse drug reactions may emerge in the infant, although they are rarely reported. Disposition of maternal drugs in breast milk is described with several key parameters, which include relative infant dose (RID): infant drug intake via milk (weight- and time-adjusted) expressed as a percentage of the similarly adjusted mother's dose. Most drugs show RID values of <10%, indicating that drug concentrations in infant serum do not reach a level known to be therapeutic in adults unless drug clearance is markedly lower than the adult level on a weight basis. RID is a function of milk-to-(maternal) plasma drug concentration ratio (MP ratio) and maternal drug clearance. Therefore, MP ratio between drugs must be interpreted not by itself but with maternal drug clearance of each drug. This is why some drugs such as phenobarbital show an MP ratio of <1 but an RID as high as 50-70%, while morphine shows an MP ratio of 2 but an RID in the range of 5%. Using RID, we interpreted case reports of infant adverse outcomes, and we observed cases with relatively low infant serum concentrations of drug, consistent with low RID, as well as those with near- or above-adult therapeutic serum concentrations, with or without increased drug intake (i.e. high RID). It is important to consider both pharmacokinetic and pharmacodynamic factors in interpreting adverse outcomes in infants breastfed by a mother taking medications.
Collapse
Affiliation(s)
- Ruud H J Verstegen
- Division of Clinical Pharmacology and Toxicology, Department of Paediatrics, The Hospital for Sick Children, Toronto, Ontario, Canada
| | - Philip O Anderson
- Division of Clinical Pharmacy, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego, La Jolla, California, USA
| | - Shinya Ito
- Division of Clinical Pharmacology and Toxicology, Department of Paediatrics, The Hospital for Sick Children, Toronto, Ontario, Canada.,Department of Pharmacology and Toxicology, University of Toronto, Toronto, Ontario, Canada
| |
Collapse
|
15
|
Ghazanfarpour M, Najafi MN, Roozbeh N, Mashhadi ME, Keramat-Roudi A, Mégarbane B, Tsatsakis A, Moghaddam MMM, Rezaee R. Therapeutic approaches for neonatal abstinence syndrome: a systematic review of randomized clinical trials. ACTA ACUST UNITED AC 2019; 27:423-431. [PMID: 31093953 DOI: 10.1007/s40199-019-00266-3] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2019] [Accepted: 04/11/2019] [Indexed: 11/25/2022]
Abstract
Neonatal abstinence syndrome (NAS) which is observed in 55-94% of the newborns from opioids-taking mothers produces deleterious neurological symptoms. Various pharmacological therapies have been investigated in neonates with NAS. This article reviews all studies on NAS treatment to analyze the duration of treatment, length of hospitalization and possible drug adverse effects. The search was limited to the randomized clinical trials which examined the treatments of neonates with NAS. Scientific databases including PubMed, Cochrane Library, ISI Web of Science, Embase and Scopus were systematically searched. Retrieved articles were reviewed by two researchers and evaluated using the JADAD scoring system. Finally, the treatment duration, hospitalization length and drug side-effects were extracted. Methadone, buprenorphine and clonidine were found more effective than morphine. Diluted tincture of opium (DTO) in combination with phenobarbital or clonidine was significantly more effective than DTO alone. Clonidine was a significantly better adjunctive therapy than phenobarbital in reducing morphine treatment days. No significant difference was observed between morphine and DTO effectiveness. Deciding the optimal regimen to manage symptomatic NAS, as a single or an adjunct therapy is not possible based on the literature, due to the low quality, small size and short-term treatment considered in the published studies. Graphical abstract Process of selecting trials included in the present systematic review.
Collapse
Affiliation(s)
- Masumeh Ghazanfarpour
- Department of Nursing and Midwifery, Razi School of Nursing and Midwifery, Kerman University of Medical Sciences, Kerman, Iran
| | - Mona Najaf Najafi
- Clinical Research Unit, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Nasibeh Roozbeh
- Mother and Child Welfare Research Center, Hormozgan University of Medical Sciences, Bandar Abbas, Iran
| | | | - Atefeh Keramat-Roudi
- Student Research Committee, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Bruno Mégarbane
- Department of Medical and Toxicological Critical Care, Paris-Diderot University, INSERM UMRS-1144, Paris, France
| | - Aristidis Tsatsakis
- Center of Toxicology Science & Research, Medical School, University of Crete, Heraklion, Crete, Greece
| | | | - Ramin Rezaee
- Clinical Research Unit, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran.
- Neurogenic Inflammation Research Center, Mashhad University of Medical Sciences, Mashhad, Iran.
- Aristotle University of Thessaloniki, Department of Chemical Engineering, Environmental Engineering Laboratory, University Campus, Thessaloniki, 54124, Greece.
- HERACLES Research Center on the Exposome and Health, Center for Interdisciplinary Research and Innovation, Bldg. B, 10th km Thessaloniki-Thermi Road, Thessaloniki, 57001, Greece.
| |
Collapse
|
16
|
Abstract
BACKGROUND Antiepileptic drugs (AEDs) are the mainstay of epilepsy treatment. Since 1989, 18 new AEDs have been licensed for clinical use and there are now 27 licensed AEDs in total for the treatment of patients with epilepsy. Furthermore, several AEDs are also used for the management of other medical conditions, for example, pain and bipolar disorder. This has led to an increasingly widespread application of therapeutic drug monitoring (TDM) of AEDs, making AEDs among the most common medications for which TDM is performed. The aim of this review is to provide an overview of the indications for AED TDM, to provide key information for each individual AED in terms of the drug's prescribing indications, key pharmacokinetic characteristics, associated drug-drug pharmacokinetic interactions, and the value and the intricacies of TDM for each AED. The concept of the reference range is discussed as well as practical issues such as choice of sample types (total versus free concentrations in blood versus saliva) and sample collection and processing. METHODS The present review is based on published articles and searches in PubMed and Google Scholar, last searched in March 2018, in addition to references from relevant articles. RESULTS In total, 171 relevant references were identified and used to prepare this review. CONCLUSIONS TDM provides a pragmatic approach to epilepsy care, in that bespoke dose adjustments are undertaken based on drug concentrations so as to optimize clinical outcome. For the older first-generation AEDs (carbamazepine, ethosuximide, phenobarbital, phenytoin, primidone, and valproic acid), much data have accumulated in this regard. However, this is occurring increasingly for the new AEDs (brivaracetam, eslicarbazepine acetate, felbamate, gabapentin, lacosamide, lamotrigine, levetiracetam, oxcarbazepine, perampanel, piracetam, pregabalin, rufinamide, stiripentol, sulthiame, tiagabine, topiramate, vigabatrin, and zonisamide).
Collapse
|
17
|
The effectiveness of phenobarbital in patients with refractory status epilepticus undergoing therapeutic plasma exchange. Neuroreport 2019; 29:1360-1364. [PMID: 30216211 DOI: 10.1097/wnr.0000000000001119] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
This study aimed to elucidate the therapeutic concentration range of phenobarbital (PB) for adults, as well as the influence of therapeutic plasma exchange (TPE) on plasma concentration of PB. We retrospectively reviewed consecutive patients diagnosed with refractory status epileptic (RSE) and treated with a bolus injection of PB as well as TPE, admitted to our neurocritical care unit from November 2015 to October 2016. Continuous electroencephalographic monitoring was performed routinely for these patients. TPE was performed using a continuous-flow cell separator. PB concentrations in the plasma and cerebrospinal fluid were measured by gas chromatography-mass spectrometer analysis before and after TPE. A total of seven patients were included; among these, one patient had RSE related to anti-N-methyl-D-aspartate receptor encephalitis, another patient had Hashimoto encephalopathy, and five patients had undetermined etiology. For patients with clinical and electrographic control (n=6), the plasma concentration of PB ranged from 138 to 243.7 μg/ml. In addition, of six paired plasma samples (before and after TPE) obtained from three patients, no significant differences between the concentrations of PB were detected (P=0.6), suggesting that TPE may not significantly affect the plasma concentration of PB. This study confirmed that PB more than 100 µg/ml was effective for adults with RSE. Moreover, TPE may not have an influence on the plasma concentration of PB.Video abstract: http://links.lww.com/WNR/A489.
Collapse
|
18
|
Ravishankar N, Nuoman R, Amuluru K, El-Ghanem M, Thulasi V, Dangayach NS, Lee K, Al-Mufti F. Management Strategies for Intracranial Pressure Crises in Subarachnoid Hemorrhage. J Intensive Care Med 2018; 35:211-218. [PMID: 30514150 DOI: 10.1177/0885066618813073] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Objectives: Standard management strategies for lowering intracranial pressure (ICP) in traumatic brain injury has been well-studied, but the use of lesser known interventions for ICP in subarachnoid hemorrhage (SAH) remains elusive. Searches were performed in PubMed and EBSCO Host to identify best available evidence for evaluation and management of medically refractory ICP in SAH. The role of standard management strategies such as head elevation, hyperventilation, mannitol and hypertonic saline as well as lesser known management such as sodium bicarbonate, indomethacin, tromethamine, decompressive craniectomy, decompressive laparotomy, hypothermia, and barbiturate coma are reviewed. We also included dose concentrations, dose frequency, infusion volume, and infusion rate for these lesser known strategies. Nonetheless, there is still a gap in the evidence to recommend optimal dosing, timing and its role in the improvement of outcomes but early diagnosis and appropriate management reduce adverse outcomes.
Collapse
Affiliation(s)
- Nidhi Ravishankar
- Department of Neurology, Windsor University School of Medicine, Frankfort, IL, USA
| | - Rolla Nuoman
- Department of Neurointerventional Radiology, University of Pittsburgh, Hamot, Erie, PA, USA.,Department of Neurology, Rutgers University-New Jersey Medical School, Newark, NJ, USA
| | - Krishna Amuluru
- Department of Neurointerventional Radiology, University of Pittsburgh, Hamot, Erie, PA, USA.,Department of Neurology, Division of Neuroendovascular Surgery and Neurocritical Care, Rutgers University-Robert Wood Johnson Medical School, New Brunswick, NJ, USA
| | - Mohammad El-Ghanem
- Department of Neurology, Division of Neuroendovascular Surgery and Neurocritical Care, Rutgers University-Robert Wood Johnson Medical School, New Brunswick, NJ, USA.,Department of Neurosurgery, Rutgers University-New Jersey Medical School, Newark, NJ, USA
| | - Venkatraman Thulasi
- Department of Neurology, Rutgers University-New Jersey Medical School, Newark, NJ, USA
| | - Neha S Dangayach
- Departments of Neurology and Neurosurgery, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Kiwon Lee
- Department of Neurology, University of Texas Health, Houston, TX, USA
| | - Fawaz Al-Mufti
- Department of Neurology, Division of Neuroendovascular Surgery and Neurocritical Care, Rutgers University-Robert Wood Johnson Medical School, New Brunswick, NJ, USA.,Department of Neurosurgery, Rutgers University-New Jersey Medical School, Newark, NJ, USA
| |
Collapse
|
19
|
Gangurde PK, Ajitkumar B. N, Kumar L. Lamotrigine Lipid Nanoparticles for Effective Treatment of Epilepsy: a Focus on Brain Targeting via Nasal Route. J Pharm Innov 2018. [DOI: 10.1007/s12247-018-9343-z] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
|
20
|
Alotaibi NM, Wang JZ, Pasarikovski CR, Guha D, Al-Mufti F, Mamdani M, Saposnik G, Schweizer TA, Macdonald RL. Management of raised intracranial pressure in aneurysmal subarachnoid hemorrhage: time for a consensus? Neurosurg Focus 2018; 43:E13. [PMID: 29088956 DOI: 10.3171/2017.7.focus17426] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Elevated intracranial pressure (ICP) is a well-recognized phenomenon in aneurysmal subarachnoid hemorrhage (aSAH) that has been demonstrated to lead to poor outcomes. Despite significant advances in clinical research into aSAH, there are no consensus guidelines devoted specifically to the management of elevated ICP in the setting of aSAH. To treat high ICP in aSAH, most centers extrapolate their treatment algorithms from studies and published guidelines for traumatic brain injury. Herein, the authors review the current management strategies for treating raised ICP within the aSAH population, emphasize key differences from the traumatic brain injury population, and highlight potential directions for future research in this controversial topic.
Collapse
Affiliation(s)
- Naif M Alotaibi
- Institute of Medical Science, Faculty of Medicine, University of Toronto, and.,Department of Neurosurgery, National Neuroscience Institute, King Fahad Medical City, Riyadh, Saudi Arabia
| | - Justin Z Wang
- Division of Neurosurgery, Department of Surgery, St Michael's Hospital, University of Toronto, Ontario, Canada
| | - Christopher R Pasarikovski
- Division of Neurosurgery, Department of Surgery, St Michael's Hospital, University of Toronto, Ontario, Canada
| | - Daipayan Guha
- Institute of Medical Science, Faculty of Medicine, University of Toronto, and.,Division of Neurosurgery, Department of Surgery, St Michael's Hospital, University of Toronto, Ontario, Canada
| | - Fawaz Al-Mufti
- Department of Neurology and Critical Care, Robert Wood Johnson University Hospital, New Brunswick, New Jersey; and
| | - Muhammad Mamdani
- Li Ka Shing Centre for Healthcare Analytics Research and Training, Institute for Clinical Evaluative Sciences
| | - Gustavo Saposnik
- Neuroscience Research Program, Keenan Research Centre of the Li Ka Shing Knowledge Institute of St. Michael's Hospital; and.,Stroke Outcomes and Decision Neuroscience Research Unit, St. Michael's Hospital, University of Toronto, Ontario, Canada
| | - Tom A Schweizer
- Institute of Medical Science, Faculty of Medicine, University of Toronto, and.,Division of Neurosurgery, Department of Surgery, St Michael's Hospital, University of Toronto, Ontario, Canada.,Neuroscience Research Program, Keenan Research Centre of the Li Ka Shing Knowledge Institute of St. Michael's Hospital; and
| | - R Loch Macdonald
- Institute of Medical Science, Faculty of Medicine, University of Toronto, and.,Division of Neurosurgery, Department of Surgery, St Michael's Hospital, University of Toronto, Ontario, Canada.,Neuroscience Research Program, Keenan Research Centre of the Li Ka Shing Knowledge Institute of St. Michael's Hospital; and
| |
Collapse
|
21
|
Nakayama H, Echizen H, Ogawa R, Orii T, Kato T. Reduced Clearance of Phenobarbital in Advanced Cancer Patients near the End of Life. Eur J Drug Metab Pharmacokinet 2018; 44:77-82. [PMID: 30027304 DOI: 10.1007/s13318-018-0495-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
BACKGROUND AND OBJECTIVES Little is known about the pharmacokinetics of phenobarbital in terminally ill cancer patients. We investigated whether phenobarbital clearance alters depending on the length of survival. METHODS We retrospectively reviewed the clinical, laboratory, and therapeutic drug monitoring (TDM) records of patients who received parenteral or oral phenobarbital for 21 consecutive days or longer between 2000 and 2016. Patients were divided into non-cancer and cancer groups. Cancer patients were further stratified according to the survival interval after TDM: those who survived > 3 months were classified as long-surviving and the remainders short-surviving cancer patients. Phenobarbital clearance (CLPB) was calculated at steady state. Multiple comparisons of median CLPB were conducted among the three groups. RESULTS Data were collected from 44 non-cancer patients and 34 cancer patients comprising 24 long-surviving and 10 short-surviving cancer patients. Among 10 short-surviving cancer patients, 4 had hepatic metastasis. Median CLPB (range) in short-surviving cancer patients [0.076 (0.057‒0.114) L/kg/day] was significantly (p < 0.05) lower than that in non-cancer patients [0.105 (0.060‒0.226) L/kg/day] and in long-surviving cancer patients [0.100 (0.082‒0.149) L/kg/day]. CONCLUSION Terminally ill patients with advanced cancer may have reduced CLPB, thereby TDM is recommended for these patients particularly near the end of life.
Collapse
Affiliation(s)
- Hirokazu Nakayama
- Department of Pharmacy, NTT Medical Centre Tokyo, 5-9-22 Higashi-gotanda, Shinagawa-ku, Tokyo, 141-8625, Japan.
| | - Hirotoshi Echizen
- Department of Pharmacotherapy, Meiji Pharmaceutical University, 2-522-1 Noshio, Kiyose, Tokyo, 204-8588, Japan
| | - Ryuichi Ogawa
- Department of Pharmacotherapy, Meiji Pharmaceutical University, 2-522-1 Noshio, Kiyose, Tokyo, 204-8588, Japan
| | - Takao Orii
- Department of Pharmacy, NTT Medical Centre Tokyo, 5-9-22 Higashi-gotanda, Shinagawa-ku, Tokyo, 141-8625, Japan
| | - Toshiaki Kato
- Department of Pharmacy, NTT Medical Centre Tokyo, 5-9-22 Higashi-gotanda, Shinagawa-ku, Tokyo, 141-8625, Japan
| |
Collapse
|
22
|
Moffett BS, Weingarten MM, Galati M, Placencia JL, Rodman EA, Riviello JJ, Kayyal SY. Phenobarbital population pharmacokinetics across the pediatric age spectrum. Epilepsia 2018; 59:1327-1333. [PMID: 29897629 DOI: 10.1111/epi.14447] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/16/2018] [Indexed: 11/29/2022]
Abstract
OBJECTIVE Phenobarbital is frequently used in pediatric patients for treatment and prophylaxis of seizures. Pharmacokinetic data for this patient population is lacking and would assist in dosing decisions. METHODS A retrospective population pharmacokinetic analysis was designed for all pediatric patients <19 years of age initiated on phenobarbital at our institution from January 2011 to June 2017. Patients were included if they were initiated on intravenous or enteral phenobarbital for treatment or prophylaxis of seizures and had a serum phenobarbital concentration monitored while an inpatient. Data collection included the following: age, weight, height, gestational age, core body temperature, serum creatinine, blood urea nitrogen, aspartase aminotransferase, alanine aminotransferase, urine output over the prior 12 hours, phenobarbital doses and serum concentrations, and potential drug-drug interactions. Descriptive statistical methods were used to summarize the data. Pharmacokinetic analysis was performed with NONMEM and simulation was performed for doses of 10, 20, 30, and 40 mg kg-1 dose-1 , iv, followed by enteral doses of 3, 4, 5, and 6 mg kg-1 d-1 . RESULTS A total of 355 patients (50.3% male, median gestational age 39 weeks (interquartile range [IQR] 35, 40), median age 0.28 years (IQR 0.06, 0.82). Median phenobarbital dose was enteral = 2.6 (IQR 1.9, 3.9) mg kg-1 dose-1 ; intravenous = 2.6 (IQR 2.2, 4.9) mg kg-1 dose-1 ) and mean serum concentration was 41.1 ± 23.9 mg/L at median 6.5 (IQR 2.9, 11.1) hours after a dose. A one-compartment proportional error model best fit the data where clearance and volume of distribution were allometrically scaled using fat-free mass. Significant covariates included serum creatinine, postmenstrual age, and drug-drug interactions on clearance, and age in years on volume of distribution. SIGNIFICANCE Phenobarbital dosing of 30 mg kg-1 dose-1 ,iv, followed by 4 mg kg-1 d-1 had the highest probability of attaining a therapeutic concentration at 7 days. Postmenstrual age and drug-drug interactions should be incorporated into dosing decisions.
Collapse
Affiliation(s)
- Brady S Moffett
- Department of Pharmacy, Texas Children's Hospital, Houston, TX, USA.,Department of Pediatrics, Baylor College of Medicine, Houston, TX, USA
| | - Mindl M Weingarten
- Department of Pharmacy, Texas Children's Hospital, Houston, TX, USA.,Department of Pediatrics, Baylor College of Medicine, Houston, TX, USA
| | | | - Jennifer L Placencia
- Department of Pharmacy, Texas Children's Hospital, Houston, TX, USA.,Department of Pediatrics, Baylor College of Medicine, Houston, TX, USA
| | - Emily A Rodman
- Department of Pharmacy, Texas Children's Hospital, Houston, TX, USA.,Department of Pediatrics, Baylor College of Medicine, Houston, TX, USA
| | - James J Riviello
- Department of Pediatrics, Baylor College of Medicine, Houston, TX, USA
| | - Simon Y Kayyal
- Department of Pediatrics, Baylor College of Medicine, Houston, TX, USA
| |
Collapse
|
23
|
Hammond DA, Rowe JM, Wong A, Wiley TL, Lee KC, Kane-Gill SL. Patient Outcomes Associated With Phenobarbital Use With or Without Benzodiazepines for Alcohol Withdrawal Syndrome: A Systematic Review. Hosp Pharm 2017; 52:607-616. [PMID: 29276297 DOI: 10.1177/0018578717720310] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Purpose: Benzodiazepines are the drug of choice for alcohol withdrawal syndrome (AWS); however, phenobarbital is an alternative agent used with or without concomitant benzodiazepine therapy. In this systematic review, we evaluate patient outcomes with phenobarbital for AWS. Methods: Medline, Cochrane Library, and Scopus were searched from 1950 through February 2017 for controlled trials and observational studies using ["phenobarbital" or "barbiturate"] and ["alcohol withdrawal" or "delirium tremens."] Risk of bias was assessed using tools recommended by National Heart, Lung, and Blood Institute. Results: From 294 nonduplicative articles, 4 controlled trials and 5 observational studies (n = 720) for AWS of any severity were included. Studies were of good quality (n = 2), fair (n = 4), and poor (n = 3). In 6 studies describing phenobarbital without concomitant benzodiazepine therapy, phenobarbital decreased AWS symptoms (P < .00001) and displayed similar rates of treatment failure versus comparator therapies (38% vs 29%). A study with 2 cohorts showed similar rates of intensive care unit (ICU) admission (phenobarbital: 16% and 9% vs benzodiazepine: 14%) and hospital length of stay (phenobarbital: 5.85 and 5.30 days vs benzodiazepine: 6.64 days). In 4 studies describing phenobarbital with concomitant benzodiazepine therapy, phenobarbital groups had similar ICU admission rates (8% vs 25%), decreased mechanical ventilation (21.9% vs 47.3%), decreased benzodiazepine requirements by 50% to 90%, and similar ICU and hospital lengths of stay and AWS symptom resolution versus comparator groups. Adverse effects with phenobarbital, including dizziness and drowsiness, rarely occurred. Conclusion: Phenobarbital, with or without concomitant benzodiazepines, may provide similar or improved outcomes when compared with alternative therapies, including benzodiazepines alone.
Collapse
Affiliation(s)
| | - Jordan M Rowe
- University of Tennessee Medical Center, Knoxville, USA
| | - Adrian Wong
- Brigham and Women's Hospital, Boston, MA, USA
| | | | | | | |
Collapse
|
24
|
Heo G, Kim SH, Chang MJ. Effect of ketogenic diet and other dietary therapies on anti-epileptic drug concentrations in patients with epilepsy. J Clin Pharm Ther 2017. [PMID: 28626875 DOI: 10.1111/jcpt.12578] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
WHAT IS KNOWN AND OBJECTIVE The ketogenic diet (KD) is an effective high-fat, adequate-protein, low-carbohydrate diet for patients with refractory epilepsy. The aim of this study was to investigate the potential effects of the KD and other dietary therapies on the concentrations of anticonvulsants in patients with epilepsy. METHODS Patients with epilepsy who were treated with the KD and other dietary therapies for more than 30 days with at least one measurement performed both before and during the diet were evaluated. The mean serum concentrations and the mean serum concentrations per weight per daily dose per bioavailability (F) of anti-epileptic drugs (AEDs) before and during the treatment were assessed. We also compared the rates of events out of reference ranges of the AEDs between before and during the KD and other dietary therapies. We compared the serum albumin, alanine transaminase and aspartate transaminase data of patients with valproic acid before and during the KD. RESULTS AND DISCUSSION One-hundred thirty-nine patients including 81 male patients were enrolled. The median age of the patients was 2.91 (0.15-15.46) years. The median duration of the dietary therapies was 153 (35-2307) days. After the dietary therapies, the serum concentrations of carbamazepine, lamotrigine, levetiracetam, topiramate and valproic acid decreased, whereas that of phenobarbital slightly increased. However, statistical significance was found only with valproic acid (67.07±25.89 μg/mL vs 51.00±20.19 μg/mL, P<.05). The serum concentrations per weight per daily dose per drug F significantly decreased for valproic acid (1.38±1.39×10-2 vs 0.82±0.82×10-2 μg d mL-1 F-1 ) and phenobarbital (6.66±7.20×10-2 vs 4.75±4.07×10-2 μg d mL-1 F-1 , P<.05). The rate of occurrence of events out of reference ranges significantly increased with valproic acid (36.08% vs 57.23%, P<.05). WHAT IS NEW AND CONCLUSIONS Most anti-epileptic drug serum concentrations remained stable during the KD and other related dietary therapies except those of valproic acid. Therefore, serum concentrations of valproic acid should be monitored when the KD and other dietary therapies are concomitantly administered.
Collapse
Affiliation(s)
- G Heo
- Department of Pharmaceutical Medicine and Regulatory Science, College of Medicine and Pharmacy, Yonsei University, Incheon, Korea
| | - S H Kim
- Division of Pediatric Neurology, Department of Pediatrics, Severance Children's Hospital, Yonsei University College of Medicine, Seoul, Korea
| | - M J Chang
- Department of Pharmaceutical Medicine and Regulatory Science, College of Medicine and Pharmacy, Yonsei University, Incheon, Korea.,Department of Pharmacy, College of Pharmacy, Yonsei Institute of Pharmaceutical Sciences, Yonsei University, Incheon, Korea
| |
Collapse
|
25
|
Völler S, Flint RB, Stolk LM, Degraeuwe PLJ, Simons SHP, Pokorna P, Burger DM, de Groot R, Tibboel D, Knibbe CAJ. Model-based clinical dose optimization for phenobarbital in neonates: An illustration of the importance of data sharing and external validation. Eur J Pharm Sci 2017; 109S:S90-S97. [PMID: 28506869 DOI: 10.1016/j.ejps.2017.05.026] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2017] [Accepted: 05/11/2017] [Indexed: 11/27/2022]
Abstract
BACKGROUND Particularly in the pediatric clinical pharmacology field, data-sharing offers the possibility of making the most of all available data. In this study, we utilize previously collected therapeutic drug monitoring (TDM) data of term and preterm newborns to develop a population pharmacokinetic model for phenobarbital. We externally validate the model using prospective phenobarbital data from an ongoing pharmacokinetic study in preterm neonates. METHODS TDM data from 53 neonates (gestational age (GA): 37 (24-42) weeks, bodyweight: 2.7 (0.45-4.5) kg; postnatal age (PNA): 4.5 (0-22) days) contained information on dosage histories, concentration and covariate data (including birth weight, actual weight, post-natal age (PNA), postmenstrual age, GA, sex, liver and kidney function, APGAR-score). Model development was carried out using NONMEM® 7.3. After assessment of model fit, the model was validated using data of 17 neonates included in the DINO (Drug dosage Improvement in NeOnates)-study. RESULTS Modelling of 229 plasma concentrations, ranging from 3.2 to 75.2mg/L, resulted in a one compartment model for phenobarbital. Clearance (CL) and volume (Vd) for a child with a birthweight of 2.6kg at PNA day 4.5 was 0.0091L/h (9%) and 2.38L (5%), respectively. Birthweight and PNA were the best predictors for CL maturation, increasing CL by 36.7% per kg birthweight and 5.3% per postnatal day of living, respectively. The best predictor for the increase in Vd was actual bodyweight (0.31L/kg). External validation showed that the model can adequately predict the pharmacokinetics in a prospective study. CONCLUSION Data-sharing can help to successfully develop and validate population pharmacokinetic models in neonates. From the results it seems that both PNA and bodyweight are required to guide dosing of phenobarbital in term and preterm neonates.
Collapse
Affiliation(s)
- Swantje Völler
- Division of Pharmacology, Leiden Academic Center for Drug Research, Gorlaeus Laboratories, Einsteinweg 55, 2333 CC Leiden, The Netherlands.
| | - Robert B Flint
- Department of Pediatrics, Division of Neonatology, Erasmus MC - Sophia Children's Hospital, Rotterdam, The Netherlands; Department of Pharmacy, Radboud Institute for Health Sciences, Radboud University Medical Center, Nijmegen, The Netherlands; Department of Pharmacy, Erasmus Medical Center, Rotterdam, The Netherlands
| | - Leo M Stolk
- Department of Clinical Pharmacy, Maastricht UMC, The Netherlands
| | - Pieter L J Degraeuwe
- Department of Pediatrics, Division of Neonatology, Maastricht UMC, Maastricht, The Netherlands
| | - Sinno H P Simons
- Department of Pediatrics, Division of Neonatology, Erasmus MC - Sophia Children's Hospital, Rotterdam, The Netherlands
| | - Paula Pokorna
- Department of Pediatrics - PICU/NICU, General University Hospital, 1st Faculty of Medicine Charles University, Prague, Czech Republic; Department of Pharmacology, General University Hospital, 1st Faculty of Medicine Charles University, Prague, Czech Republic; Intensive Care, Department of Pediatric Surgery, Department of Pediatrics, Erasmus MC - Sophia Children's Hospital, Rotterdam, The Netherlands
| | - David M Burger
- Department of Pharmacy, Radboud Institute for Health Sciences, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Ronald de Groot
- Laboratory of Pediatric Infectious Diseases, Department of Pediatrics, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Dick Tibboel
- Intensive Care, Department of Pediatric Surgery, Department of Pediatrics, Erasmus MC - Sophia Children's Hospital, Rotterdam, The Netherlands
| | - Catherijne A J Knibbe
- Division of Pharmacology, Leiden Academic Center for Drug Research, Gorlaeus Laboratories, Einsteinweg 55, 2333 CC Leiden, The Netherlands; Department of Clinical Pharmacy, St. Antonius Hospital, Nieuwegein, The Netherlands
| | | |
Collapse
|
26
|
Abstract
Therapeutic drug monitoring is widely used in the anticonvulsant treatment of persons with epilepsy. Most monitoring uses serum, but many anticonvulsant drugs can as easily be monitored using saliva, including phenobarbital, phenytoin, carbamazepine, lamotrigine, oxcarbazepine, topiramate, levetiracetam, and gabapentin. For highly protein-bound medications such as phenobarbital, phenytoin, and carbamazepine, saliva has the advantage of providing an approximation of the serum free level, the free level presumably being the active moiety. Salivary therapeutic drug monitoring offers a number of advantages over serum therapeutic drug monitoring, including lack of pain, lower cost, and wide potential acceptability by patients and physicians. It has the potential to open new approaches to treatment with strategic at-home monitoring at the time a seizure or adverse event occurs and to allow the collection of cohort-based, pharmacokinetic, and pharmcodynamic data for populations of persons of varying ages and with different medical conditions who require anticonvulsant medications.
Collapse
Affiliation(s)
- Robert J. Baumann
- Department of Neurology, Kentucky Clinic, College of Medicine, University of Kentucky, Lexington, Kentucky, baumann @uky.edu
| |
Collapse
|
27
|
Abstract
Intravenous and intramuscular antiseizure drugs (ASDs) are essential in the treatment of clinical seizure emergencies as well as in replacement therapy when oral administration is not possible. The parenteral formulations provide rapid delivery and complete (intravenous) or nearly complete (intramuscular) bioavailability. Controlled administration of the ASD is feasible with intravenous but not intramuscular formulations. This article reviews the literature and discusses the chemistry, pharmacology, pharmacokinetics, and clinical use of currently available intravenous and intramuscular ASD formulations as well as the development of new formulations and agents. Intravenous or intramuscular formulations of lorazepam, diazepam, midazolam, and clonazepam are typically used as the initial treatment agents in seizure emergencies. Recent studies also support the use of intramuscular midazolam as easier than the intravenous delivery of lorazepam in the pre-hospital setting. However, benzodiazepines may be associated with hypotension and respiratory depression. Although loading with intravenous phenytoin was an early approach to treatment, it is associated with cardiac arrhythmias, hypotension, and tissue injury at the injection site. This has made it less favored than fosphenytoin, a water-soluble, phosphorylated phenytoin molecule. Other drugs being used for acute seizure emergencies are intravenous formulations of valproic acid, levetiracetam, and lacosamide. However, the comparative effectiveness of these for status epilepticus (SE) has not been evaluated adequately. Consequently, guidelines for the medical management of SE continue to recommend lorazepam followed by fosphenytoin, or phenytoin if fosphenytoin is not available. Intravenous solutions for carbamazepine, lamotrigine, and topiramate have been developed but remain investigational. The current ASDs were not developed for use in emergency situations, but were adapted from ASDs approved for chronic oral use. New approaches for bringing drugs from experimental models to treatment of human SE are needed.
Collapse
|
28
|
Abstract
Patients with refractory intracranial pressure represent a challenge to the multidisciplinary critical care team. Myriad diagnoses: traumatic brain injury, subarachnoid hemorrhage, intracranial hemorrhage, and ischemic stroke, are among the causes commonly seen in patients with elevated intracranial pressure. Clinicians tasked with caring for these patients must be aware of available interventions and management strategies to improve outcomes. Nurses as the bedside clinician most frequently assessing these patients are ideally situated to detect changes and act efficiently to lower refractory intracranial pressure.
Collapse
Affiliation(s)
- Jennifer D Robinson
- Neuroscience, Yale New Haven Hospital, 360 State Street #1207, New Haven, CT 06510, USA.
| |
Collapse
|
29
|
Leppik IE, Patel SI. Intramuscular and rectal therapies of acute seizures. Epilepsy Behav 2015; 49:307-12. [PMID: 26071998 DOI: 10.1016/j.yebeh.2015.05.001] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/22/2015] [Accepted: 05/01/2015] [Indexed: 11/16/2022]
Abstract
The intramuscular (IM) and rectal routes are alternative routes of delivery for antiepileptic drugs (AEDs) when the intravenous route is not practical or possible. For treatment of acute seizures, the AED used should have a short time to maximum concentration (Tmax). Some AEDs have preparations that may be given intramuscularly. These include the benzodiazepines (diazepam, lorazepam, and midazolam) and others (fosphenytoin, levetiracetam). Although phenytoin and valproate have parenteral preparations, these should not be given intramuscularly. A recent study of prehospital treatment of status epilepticus evaluated a midazolam (MDZ) autoinjector delivering IM drug compared to IV lorazepam (LZP). Seizures were absent on arrival to the emergency department in 73.4% of the IM MDZ compared to a 63.4% response in LZP-treated subjects (p < 0.001 for superiority). Almost all AEDs have been evaluated for rectal administration as solutions, gels, and suppositories. In a placebo-controlled study, diazepam (DZP) was administered at home by caregivers in doses that ranged from 0.2 to 0.5 mg/kg. Diazepam was superior to placebo in reduced seizure frequency in children (p < 0.001) and in adults (p = 0.02) and time to recurrent seizures after an initial treatment (p < 0.001). Thus, at this time, only MZD given intramuscularly and DZP given rectally appear to have the properties required for rapid enough absorption to be useful when intravenous routes are not possible. Some drugs cannot be administered rectally owing to factors such as poor absorption or poor solubility in aqueous solutions. The relative rectal bioavailability of gabapentin, oxcarbazepine, and phenytoin is so low that the current formulations are not considered to be suitable for administration by this route. When administered as a solution, diazepam is rapidly absorbed rectally, reaching the Tmax within 5-20 min in children. By contrast, rectal administration of lorazepam is relatively slow, with a Tmax of 1-2h. The dependence of gabapentin on an active transport system, and the much-reduced surface area of the rectum compared with the small intestine, may be responsible for its lack of absorption from the rectum. This article is part of a Special Issue entitled "Status Epilepticus".
Collapse
Affiliation(s)
- Ilo E Leppik
- Department of Experimental and Clinical Pharmacology, College of Pharmacy, University of Minnesota, Minneapolis, MN, USA; MINCEP Epilepsy Care, University of Minnesota Physicians, Minneapolis, MN, USA; Department of Neurology, University of Minnesota Medical School, Minneapolis, MN, USA.
| | - Sima I Patel
- MINCEP Epilepsy Care, University of Minnesota Physicians, Minneapolis, MN, USA; Department of Neurology, University of Minnesota Medical School, Minneapolis, MN, USA
| |
Collapse
|
30
|
Dried blood spots for monitoring and individualization of antiepileptic drug treatment. Eur J Pharm Sci 2015; 75:25-39. [DOI: 10.1016/j.ejps.2015.04.008] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2015] [Revised: 04/08/2015] [Accepted: 04/09/2015] [Indexed: 11/21/2022]
|
31
|
Nonlinear mixed effects modelling approach in investigating phenobarbital pharmacokinetic interactions in epileptic patients. Eur J Clin Pharmacol 2014; 71:183-90. [PMID: 25380628 DOI: 10.1007/s00228-014-1778-7] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2014] [Accepted: 10/28/2014] [Indexed: 12/14/2022]
Abstract
PURPOSE The present study aimed to establish population pharmacokinetic model for phenobarbital (PB), examining and quantifying the magnitude of PB interactions with other antiepileptic drugs concomitantly used and to demonstrate its use for individualization of PB dosing regimen in adult epileptic patients. METHODS In total 205 PB concentrations were obtained during routine clinical monitoring of 136 adult epilepsy patients. PB steady state concentrations were measured by homogeneous enzyme immunoassay. Nonlinear mixed effects modelling (NONMEM) was applied for data analyses and evaluation of the final model. RESULTS According to the final population model, significant determinant of apparent PB clearance (CL/F) was daily dose of concomitantly given valproic acid (VPA). Typical value of PB CL/F for final model was estimated at 0.314 l/h. Based on the final model, co-therapy with usual VPA dose of 1000 mg/day, resulted in PB CL/F average decrease of about 25 %, while 2000 mg/day leads to an average 50 % decrease in PB CL/F. CONCLUSIONS Developed population PB model may be used in estimating individual CL/F for adult epileptic patients and could be applied for individualizing dosing regimen taking into account dose-dependent effect of concomitantly given VPA.
Collapse
|
32
|
Abstract
Blood (serum/plasma) antiepileptic drug (AED) therapeutic drug monitoring (TDM) has proven to be an invaluable surrogate marker for individualizing and optimizing the drug management of patients with epilepsy. Since 1989, there has been an exponential increase in AEDs with 23 currently licensed for clinical use, and recently, there has been renewed and extensive interest in the use of saliva as an alternative matrix for AED TDM. The advantages of saliva include the fact that for many AEDs it reflects the free (pharmacologically active) concentration in serum; it is readily sampled, can be sampled repetitively, and sampling is noninvasive; does not require the expertise of a phlebotomist; and is preferred by many patients, particularly children and the elderly. For each AED, this review summarizes the key pharmacokinetic characteristics relevant to the practice of TDM, discusses the use of other biological matrices with particular emphasis on saliva and the evidence that saliva concentration reflects those in serum. Also discussed are the indications for salivary AED TDM, the key factors to consider when saliva sampling is to be undertaken, and finally, a practical protocol is described so as to enable AED TDM to be applied optimally and effectively in the clinical setting. Overall, there is compelling evidence that salivary TDM can be usefully applied so as to optimize the treatment of epilepsy with carbamazepine, clobazam, ethosuximide, gabapentin, lacosamide, lamotrigine, levetiracetam, oxcarbazepine, phenobarbital, phenytoin, primidone, topiramate, and zonisamide. Salivary TDM of valproic acid is probably not helpful, whereas for clonazepam, eslicarbazepine acetate, felbamate, pregabalin, retigabine, rufinamide, stiripentol, tiagabine, and vigabatrin, the data are sparse or nonexistent.
Collapse
|
33
|
Marsot A, Brevaut-Malaty V, Vialet R, Boulamery A, Bruguerolle B, Simon N. Pharmacokinetics and absolute bioavailability of phenobarbital in neonates and young infants, a population pharmacokinetic modelling approach. Fundam Clin Pharmacol 2013; 28:465-71. [PMID: 23855753 DOI: 10.1111/fcp.12042] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2012] [Revised: 03/25/2013] [Accepted: 06/05/2013] [Indexed: 11/28/2022]
Abstract
Phenobarbital is widely used for treatment of neonatal seizures. Its optimal use in neonates and young infants requires information regarding pharmacokinetics. The objective of this study is to characterize the absolute bioavailability of phenobarbital in neonates and young infants, a pharmacokinetic parameter which has not yet been investigated. Routine clinical pharmacokinetic data were retrospectively collected from 48 neonates and infants (weight: 0.7-10 kg; patient's postnatal age: 0-206 days; GA: 27-42 weeks) treated with phenobarbital, who were administered as intravenous or suspension by oral routes and hospitalized in a paediatric intensive care unit. Total mean dose of 4.6 mg/kg (3.1-10.6 mg/kg) per day was administered by 30-min infusion or by oral route. Pharmacokinetic analysis was performed using a nonlinear mixed-effect population model software). Data were modelled with an allometric pharmacokinetic model, using three-fourths scaling exponent for clearance (CL). The population typical mean [per cent relative standard error (%RSE)] values for CL, apparent volume of distribution (Vd ) and bioavailability (F) were 0.0054 L/H/kg (7%), 0.64 L/kg (15%) and 48.9% (22%), respectively. The interindividual variability of CL, Vd , F (%RSE) and residual variability (%RSE) was 17% (31%), 50% (27%), 39% (27%) and 7.2 mg/L (29%), respectively. The absolute bioavailability of phenobarbital in neonates and infants was estimated. The dose should be increased when switching from intravenous to oral administration.
Collapse
Affiliation(s)
- Amélie Marsot
- Service de Pharmacologie Médicale et Clinique, hôpital Timone, bat F, 264 Rue, Saint Pierre, 13385, Marseille Cedex 5, France
| | | | | | | | | | | |
Collapse
|
34
|
Dash A, Simmers MB, Deering TG, Berry DJ, Feaver RE, Hastings NE, Pruett TL, LeCluyse EL, Blackman BR, Wamhoff BR. Hemodynamic flow improves rat hepatocyte morphology, function, and metabolic activity in vitro. Am J Physiol Cell Physiol 2013; 304:C1053-63. [PMID: 23485712 DOI: 10.1152/ajpcell.00331.2012] [Citation(s) in RCA: 78] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
In vitro primary hepatocyte systems typically elicit drug induction and toxicity responses at concentrations much higher than corresponding in vivo or clinical plasma C(max) levels, contributing to poor in vitro-in vivo correlations. This may be partly due to the absence of physiological parameters that maintain metabolic phenotype in vivo. We hypothesized that restoring hemodynamics and media transport would improve hepatocyte architecture and metabolic function in vitro compared with nonflow cultures. Rat hepatocytes were cultured for 2 wk either in nonflow collagen gel sandwiches with 48-h media changes or under controlled hemodynamics mimicking sinusoidal circulation within a perfused Transwell device. Phenotypic, functional, and metabolic parameters were assessed at multiple times. Hepatocytes in the devices exhibited polarized morphology, retention of differentiation markers [E-cadherin and hepatocyte nuclear factor-4α (HNF-4α)], the canalicular transporter [multidrug-resistant protein-2 (Mrp-2)], and significantly higher levels of liver function compared with nonflow cultures over 2 wk (albumin ~4-fold and urea ~5-fold). Gene expression of cytochrome P450 (CYP) enzymes was significantly higher (fold increase over nonflow: CYP1A1: 53.5 ± 10.3; CYP1A2: 64.0 ± 15.1; CYP2B1: 15.2 ± 2.9; CYP2B2: 2.7 ± 0.8; CYP3A2: 4.0 ± 1.4) and translated to significantly higher basal enzyme activity (device vs. nonflow: CYP1A: 6.26 ± 2.41 vs. 0.42 ± 0.015; CYP1B: 3.47 ± 1.66 vs. 0.4 ± 0.09; CYP3A: 11.65 ± 4.70 vs. 2.43 ± 0.56) while retaining inducibility by 3-methylcholanthrene and dexamethasone (fold increase over DMSO: CYP1A = 27.33 and CYP3A = 4.94). These responses were observed at concentrations closer to plasma levels documented in vivo in rats. The retention of in vivo-like hepatocyte phenotype and metabolic function coupled with drug response at more physiological concentrations emphasizes the importance of restoring in vivo physiological transport parameters in vitro.
Collapse
Affiliation(s)
- A Dash
- HemoShear, LLC, Charlottesville, VA 22902, USA.
| | | | | | | | | | | | | | | | | | | |
Collapse
|
35
|
Darwich AS, Henderson K, Burgin A, Ward N, Whittam J, Ammori BJ, Ashcroft DM, Rostami-Hodjegan A. Trends in oral drug bioavailability following bariatric surgery: examining the variable extent of impact on exposure of different drug classes. Br J Clin Pharmacol 2013; 74:774-87. [PMID: 22463107 DOI: 10.1111/j.1365-2125.2012.04284.x] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
WHAT IS ALREADY KNOWN ABOUT THIS SUBJECT Changes to oral drug bioavailability have been observed post bariatric surgery. However, the magnitude and the direction of changes have not been assessed systematically to provide insights into the parameters governing the observed trends. Understanding these can help with dose adjustments. WHAT THIS STUDY ADDS Analysis of drug characteristics based on a biopharmaceutical classification system is not adequate to explain observed trends in altered oral drug bioavailability following bariatric surgery, although the findings suggest solubility to play an important role. AIMS To identify the most commonly prescribed drugs in a bariatric surgery population and to assess existing evidence regarding trends in oral drug bioavailability post bariatric surgery. METHODS A retrospective audit was undertaken to document commonly prescribed drugs amongst patients undergoing bariatric surgery in an NHS hospital in the UK and to assess practice for drug administration following bariatric surgery. The available literature was examined for trends relating to drug permeability and solubility with regards to the Biopharmaceutics Classification System (BCS) and main route of elimination. RESULTS No significant difference in the 'post/pre surgery oral drug exposure ratio' (ppR) was apparent between BCS class I to IV drugs, with regards to dose number (Do) or main route of elimination. Drugs classified as 'solubility limited' displayed an overall reduction as compared with 'freely soluble' compounds, as well as an unaltered and increased ppR. CONCLUSION Clinical studies establishing guidelines for commonly prescribed drugs, and the monitoring of drugs exhibiting a narrow therapeutic window or without a readily assessed clinical endpoint, are warranted. Using mechanistically based pharmacokinetic modelling for simulating the multivariate nature of changes in drug exposure may serve as a useful tool in the further understanding of postoperative trends in oral drug exposure and in developing practical clinical guidance.
Collapse
Affiliation(s)
- Adam S Darwich
- Centre of Applied Pharmacokinetic Research, School of Pharmacy and Pharmaceutical Sciences, University of Manchester, Manchester, UK
| | | | | | | | | | | | | | | |
Collapse
|
36
|
Johannessen Landmark C, Johannessen SI, Tomson T. Host factors affecting antiepileptic drug delivery-pharmacokinetic variability. Adv Drug Deliv Rev 2012; 64:896-910. [PMID: 22063021 DOI: 10.1016/j.addr.2011.10.003] [Citation(s) in RCA: 77] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2011] [Revised: 10/11/2011] [Accepted: 10/14/2011] [Indexed: 01/16/2023]
Abstract
Antiepileptic drugs (AEDs) are the mainstay in the treatment of epilepsy, one of the most common serious chronic neurological disorders. AEDs display extensive pharmacological variability between and within patients, and a major determinant of differences in response to treatment is pharmacokinetic variability. Host factors affecting AED delivery may be defined as the pharmacokinetic characteristics that determine the AED delivery to the site of action, the epileptic focus. Individual differences may occur in absorption, distribution, metabolism and excretion. These differences can be determined by genetic factors including gender and ethnicity, but the pharmacokinetics of AEDs can also be affected by age, specific physiological states in life, such as pregnancy, or pathological conditions including hepatic and renal insufficiency. Pharmacokinetic interactions with other drugs are another important source of variability in response to AEDs. Pharmacokinetic characteristics of the presently available AEDs are discussed in this review as well as their clinical implications.
Collapse
|
37
|
Dash A, Blackman BR, Wamhoff BR. Organotypic systems in drug metabolism and toxicity: challenges and opportunities. Expert Opin Drug Metab Toxicol 2012; 8:999-1014. [DOI: 10.1517/17425255.2012.693161] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
|
38
|
Ibrahim RB, Balogun RA. Medications in patients treated with therapeutic plasma exchange: prescription dosage, timing, and drug overdose. Semin Dial 2012; 25:176-89. [PMID: 22321259 DOI: 10.1111/j.1525-139x.2011.01030.x] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Therapeutic plasma exchange (TPE) is an extracorporeal process commonly used in clinical medicine for the treatment of a variety of neurological, renal, hematological, dermatological, and other diseases. Inherent to the procedure, patients' plasma removal may lead to the extraction of drugs they are concurrently receiving. This review discusses the published literature assessing TPE's influence on different drug classes' disposition and, when applicable, sets forth management recommendations in cases where the drugs are used at the usual doses and in cases of drug overdose.
Collapse
Affiliation(s)
- Rami B Ibrahim
- Department of Pharmacology and Toxicology, College of Osteopathic Medicine, Michigan State University, East Lansing, Michigan, USA
| | | |
Collapse
|
39
|
Thelen K, Coboeken K, Willmann S, Burghaus R, Dressman JB, Lippert J. Evolution of a detailed physiological model to simulate the gastrointestinal transit and absorption process in humans, Part 1: Oral solutions. J Pharm Sci 2011; 100:5324-45. [DOI: 10.1002/jps.22726] [Citation(s) in RCA: 85] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2010] [Accepted: 07/14/2011] [Indexed: 11/07/2022]
|
40
|
Lappin G, Shishikura Y, Jochemsen R, Weaver RJ, Gesson C, Brian Houston J, Oosterhuis B, Bjerrum OJ, Grynkiewicz G, Alder J, Rowland M, Garner C. Comparative pharmacokinetics between a microdose and therapeutic dose for clarithromycin, sumatriptan, propafenone, paracetamol (acetaminophen), and phenobarbital in human volunteers. Eur J Pharm Sci 2011; 43:141-50. [DOI: 10.1016/j.ejps.2011.04.009] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2010] [Revised: 02/24/2011] [Accepted: 04/12/2011] [Indexed: 11/17/2022]
|
41
|
Yukawa E, Higuchi S, Aoyama T. Phenobarbitone Population Pharmacokinetics from Routine Clinical Data: Role of Patient Characteristics for Estimating Dosing Regimens. J Pharm Pharmacol 2011; 44:755-60. [PMID: 1360529 DOI: 10.1111/j.2042-7158.1992.tb05514.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Abstract
Routine clinical pharmacokinetic data collected from patients receiving phenobarbitone have been analysed to evaluate the role of patient characteristics for estimating dosing regimens. The data were analysed using NONMEM, a computer program designed for population pharmacokinetic analysis that allows pooling of data. The pharmacokinetic model of phenobarbitone was described using a one-compartment steady-state model. The effect of a variety of developmental and demographic factors on clearance was investigated. NONMEM estimates indicated a nonlinear function of total body weight as the optimum adjustment of phenobarbitone clearance. Concomitant administration of phenobarbitone and other antiepileptic drugs showed a decrease of phenobarbitone clearance in young children. The dosing method based on clearance values obtained by NONMEM analysis allowed the prediction of the steady-state concentration as a function of maintenance dose with acceptable error for therapeutic drug monitoring.
Collapse
Affiliation(s)
- E Yukawa
- Department of Hospital Pharmacy, Kyushu University Hospital, Faculty of Medicine, Fukuoka, Japan
| | | | | |
Collapse
|
42
|
Siddiqi N, Marfo K. Clinically Significant Drug−Drug Interaction Between Tacrolimus and Phenobarbital. J Pharm Pract 2010; 23:585-9. [DOI: 10.1177/0897190010377804] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Purpose: The case of a 57-year-old male who experienced acute renal transplant rejection due to subtherapeutic tacrolimus levels as a result of drug interaction with phenobarbital. Summary: Drug interactions with tacrolimus due to its metabolism through the CYP 450 3A4 enzymatic pathway have led to several reports of altered tacrolimus levels, which can lead to acute rejection in renal transplant recipients. We describe the case of a 57-year-old male initiated on immunosuppressive therapy with tacrolimus in addition to his anticonvulsant medications. Conclusion: Upon tacrolimus dose increases, discontinuation of carbamazepine, and minimization of phenobarbital dose, effective tacrolimus trough levels were achieved in our patient. Identification and elimination of such drug−drug interactions is necessary to assure adequate immunosuppression in renal transplant recipients.
Collapse
Affiliation(s)
- Nida Siddiqi
- Montefiore Medical Center Department of Pharmacy
| | - Kwaku Marfo
- Montefiore Medical Center Department of Pharmacy
- Montefiore-Einstein Transplant Program
| |
Collapse
|
43
|
Chen ML, Yu L. The use of drug metabolism for prediction of intestinal permeability (dagger). Mol Pharm 2009; 6:74-81. [PMID: 19132929 DOI: 10.1021/mp8001864] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The Biopharmaceutics Classification System (BCS), based on the aqueous solubility and intestinal permeability of a drug substance, has been widely used to predict the extent of drug absorption during the course of pharmaceutical development. Combined with product dissolution data, this system has gained a prominent role in regulatory process to determine if a drug formulated in an immediate release solid oral dosage form qualifies for waiver of in vivo bioequivalence studies. In parallel, the Biopharmaceutics Drug Disposition Classification System (BDDCS), using aqueous solubility and drug metabolism, takes on another venue to predict overall drug disposition. It has been suggested that the matrix of drug metabolism in BDDCS can be used to substantiate the classification of permeability by BCS. A total of 51 drugs were compiled in this study to examine the use of drug metabolism for predicting permeability. All compounds were classified as high permeability based on BCS, but only 73% of the compounds were found to exhibit extensive metabolism. Lipophilicity accounts for significant metabolism of many highly permeable drugs. Fourteen (14) out of 51 drugs have poor metabolism, suggesting that high permeability as defined by BCS does not necessarily dictate extensive metabolism. The drugs that have high permeability but poor metabolism are generally hydrophilic molecules with low molecular weight and are likely to be absorbed by active transport mechanisms. Based on the present data and literature information, it seems logical to predict that the extent of absorption is mostly complete (or > or =90%) if the drug is subject to a high degree of metabolism (e.g., > or =90%). The extent of drug metabolism may be useful in supporting permeability classification under certain circumstances.
Collapse
Affiliation(s)
- Mei-Ling Chen
- Center for Drug Evaluation and Research, Food and Drug Administration, Silver Spring, MD 20993, USA.
| | | |
Collapse
|
44
|
Patsalos PN, Berry DJ, Bourgeois BFD, Cloyd JC, Glauser TA, Johannessen SI, Leppik IE, Tomson T, Perucca E. Antiepileptic drugs--best practice guidelines for therapeutic drug monitoring: a position paper by the subcommission on therapeutic drug monitoring, ILAE Commission on Therapeutic Strategies. Epilepsia 2008; 49:1239-76. [PMID: 18397299 DOI: 10.1111/j.1528-1167.2008.01561.x] [Citation(s) in RCA: 680] [Impact Index Per Article: 42.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Although no randomized studies have demonstrated a positive impact of therapeutic drug monitoring (TDM) on clinical outcome in epilepsy, evidence from nonrandomized studies and everyday clinical experience does indicate that measuring serum concentrations of old and new generation antiepileptic drugs (AEDs) can have a valuable role in guiding patient management provided that concentrations are measured with a clear indication and are interpreted critically, taking into account the whole clinical context. Situations in which AED measurements are most likely to be of benefit include (1) when a person has attained the desired clinical outcome, to establish an individual therapeutic concentration which can be used at subsequent times to assess potential causes for a change in drug response; (2) as an aid in the diagnosis of clinical toxicity; (3) to assess compliance, particularly in patients with uncontrolled seizures or breakthrough seizures; (4) to guide dosage adjustment in situations associated with increased pharmacokinetic variability (e.g., children, the elderly, patients with associated diseases, drug formulation changes); (5) when a potentially important pharmacokinetic change is anticipated (e.g., in pregnancy, or when an interacting drug is added or removed); (6) to guide dose adjustments for AEDs with dose-dependent pharmacokinetics, particularly phenytoin.
Collapse
Affiliation(s)
- Philip N Patsalos
- Institute of Neurology/The National Hospital for Neurology and Neurosurgery, London and The Chalfont Centre for Epilepsy, Chalfont St Peter, United Kingdom.
| | | | | | | | | | | | | | | | | |
Collapse
|
45
|
Odri S, Stupar M, Erös I, Antal I, Klebovich I, Szabó-Révész P, Csányi E. Transdermal delivery of phénobarbital Preformulation studies. J Drug Deliv Sci Technol 2008. [DOI: 10.1016/s1773-2247(08)50081-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
|
46
|
Lindenberg M, Kopp S, Dressman JB. Classification of orally administered drugs on the World Health Organization Model list of Essential Medicines according to the biopharmaceutics classification system. Eur J Pharm Biopharm 2005; 58:265-78. [PMID: 15296954 DOI: 10.1016/j.ejpb.2004.03.001] [Citation(s) in RCA: 493] [Impact Index Per Article: 25.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2004] [Accepted: 02/05/2004] [Indexed: 01/01/2023]
Abstract
Since its inception in 1995, the biopharmaceutical classification system (BCS) has become an increasingly important tool for regulation of drug products world-wide. Until now, application of the BCS has been partially hindered by the lack of a freely available and accurate database summarising solubility and permeability characteristics of drug substances. In this report, orally administered drugs on the Model list of Essential Medicines of the World Health Organization (WHO) are assigned BCS classifications on the basis of data available in the public domain. Of the 130 orally administered drugs on the WHO list, 61 could be classified with certainty. Twenty-one (84%) of these belong to class I (highly soluble, highly permeable), 10 (17%) to class II (poorly soluble, highly permeable), 24 (39%) to class III (highly soluble, poorly permeable) and 6 (10%) to class IV (poorly soluble, poorly permeable). A further 28 drugs could be provisionally assigned, while for 41 drugs insufficient or conflicting data precluded assignment to a specific BCS class. A total of 32 class I drugs (either certain or provisional classification) were identified. These drugs can be further considered for biowaiver status (drug product approval based on dissolution tests rather than bioequivalence studies in humans).
Collapse
Affiliation(s)
- Marc Lindenberg
- Department of Pharmaceutical Technology, Johann Wolfgang Goethe-University, Frankfurt am Main, Germany
| | | | | |
Collapse
|
47
|
Abstract
SUMMARY Phenobarbital (PB) is the most widely used antiepileptic drug (AED) in the developing world and remains a popular choice in many industrialized countries. Meta-analyses of randomized controlled trials suggest that few differences in efficacy exist between PB and other established AEDs, but its possible deleterious cognitive and behavioral side effects remain a concern in the developed world. In contrast, high degrees of efficacy and tolerability in everyday clinical use have been demonstrated consistently in observational studies in developing countries. We propose that a pragmatic, comprehensive outcomes program be carried out, perhaps under the aegis of the Global Campaign Against Epilepsy, to optimize the conditions of the use of PB, so that more people around the world can benefit from this cost-effective medication and live more fulfilling lives.
Collapse
Affiliation(s)
- Patrick Kwan
- Department of Medicine and Therapeutics, The Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, Hong Kong
| | | |
Collapse
|
48
|
Mirfazaelian A, Jahanzad F, Tabatabaei-far M, Farsam H, Mahmoudian M. Effect of smoking on single dose pharmacokinetics of phenobarbital. Biopharm Drug Dispos 2001; 22:403-6. [PMID: 11870679 DOI: 10.1002/bdd.284] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
In order to determine interaction of smoking with single dose pharmacokinetics of phenobarbital, a 60 mg tablet of the drug was given to 12 healthy male subjects in two groups (6 smokers and 6 non-smokers) in a double blind study. An HPLC method using UV detection was developed to assess phenobarbital in plasma of the subjects. Pharmacokinetic parameters were calculated and compared in the two groups. Pharmacokinetic parameters of the two groups were not significantly different in the two groups (p<0.05). The results show no considerable effect of cigarette smoking on phenobarbital pharmacokinetics, which is in agreement with enzyme studies performed previously.
Collapse
Affiliation(s)
- A Mirfazaelian
- Department of Pharmaceutics, Faculty of Pharmacy, Tehran University of Medical Sciences, P.O. Box 14155-6451, Tehran, Iran
| | | | | | | | | |
Collapse
|
49
|
Yukawa E. Population-based investigations of drug relative clearance using nonlinear mixed-effect modelling from information generated during the routine clinical care of patients. J Clin Pharm Ther 1999; 24:103-13. [PMID: 10380062 DOI: 10.1046/j.1365-2710.1999.00204.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Interpatient variability in drug disposition and response is a therapeutic premise, and thus evaluation and management of such variability are the basis for individualized pharmacotherapy. If the mathematical approach to determining drug doses were accurate and practical, the use of calculated doses could reduce the potential for toxicity and decrease the need for repetitious drug assays. The major strength of the population pharmacokinetics approach is that useful information can be extracted from sparse data collected during routine clinical care. Population pharmacokinetics can be defined as the study of the variability in serum drug concentrations between individuals when standard dosage regimens are administered. An approach to population pharmacokinetic data analysis has been implemented in the Nonlinear Mixed Effects Model (NONMEM) computer program. This report shows the feasibility of using a simple pharmacokinetic screen approach to estimate the population mean relative drug clearance and detecting drug-drug interaction by use of NONMEM. In clinical application of multiple trough screen or multiple peak screen, the variability of drug relative clearance within the population is assessed and a mathematical relationship between drug relative clearance and individual patient characteristics, such as age, body weight, gender, disease state or drug interaction with concomitant drug is derived. In this report I describe this approach and its application using several examples previously reported by us and others.
Collapse
Affiliation(s)
- E Yukawa
- Division of Pharmaceutical Sciences, Graduate School, Kyushu University, Fukuoka, Japan.
| |
Collapse
|
50
|
Alonso Gonzalez AC, Ortega Valin L, Santos Buelga D, Garcia Sanchez MJ, Santos Borbujo J, Monzon Corral L, Dominguez-Gil Hurle A. Dosage programming of phenobarbital in neonatal seizures. J Clin Pharm Ther 1993; 18:267-70. [PMID: 8227234 DOI: 10.1111/j.1365-2710.1993.tb00586.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Owing to the changes occurring in the organism as a result of biological maturation, disposition kinetics of phenobarbital in newborns is significantly different to that observed in the paediatric and adult populations. Moreover, the disposition parameters change constantly during the first days of life. The data on the serum levels of phenobarbital in 17 newborns were analysed to quantify the changes in the elimination half-life of phenobarbital during the first weeks of life. The half-life of the drug was estimated to be (mean +/- SD) 114.2 +/- 43.0 h, 73.19 +/- 24.17 h and 41.23 +/- 13.95 h in patients 1-10, 11-30 and 31-70 days old, respectively. According to these values and assuming phenobarbital serum levels of 20 mg/l to be safe and effective in neonatal seizures, the initial dosing recommended is 2.9, 4.8 and 6.0 mg/kg/day in newborns 1-10, 11-30 and 31-70 days old, respectively.
Collapse
|