Carbamazepine adverse drug reactions

The miR-23b-3p from adipose-derived stem cell exosomes alleviate inflammation in mice experiencing kainic acid-induced epileptic seizures

Epilepsy is a common neurologic disorder. While a good clinical solution is still missing, studies have confirmed that exosomes (Exos) derived from adipose-derived stem cells (ADSCs) had a therapeutic effect on various diseases, including neurological diseases. Therefore, this study aimed to reveal whether ADSC-Exo treatment could improve kainic acid (KA)-induced seizures in epileptic mice. ADSCs and Exos were isolated. Mice were generated with KA-induced epileptic seizures. ELISA was used to detect inflammatory factor expression. Luciferase reporter analysis detection showed a relationship among miR-23b-3p, STAT1, and glyoxylate reductase 1 (GlyR1). ADSC-Exos had a protective effect on KA-induced seizures by inhibiting inflammatory factor expression and the M1 microglia phenotype. The result showed that miR-23b-3p played an important role in the Exo-mediated protective effect in KA-induced seizures in epileptic mice by regulating STAT1 and GlyR1. Luciferase reporter analysis confirmed that miR-23b-3p interacted with the 3'-UTR of STAT1 and GlyR1. The miR-23b-3p inhibited M1 microglia-mediated inflammatory factor expression in microglial cells by regulating STAT1 and GlyR1. The downregulation of miR-23b-3p decreased the protective effect of ADSC-Exos on KA-induced seizures in epileptic mice. The miR-23b-3p from ADSC-Exos alleviated inflammation in mice with KA-induced epileptic seizures.

Effect of Carbamazepine on the Pharmacokinetics of Erdafitinib in Healthy Participants

Erdafitinib, a selective and potent oral pan-FGFR inhibitor, is metabolized mainly through CYP2C9 and CYP3A4 enzymes. This phase 1, open-label, single-sequence, drug-drug interaction study evaluated the pharmacokinetics, safety, and tolerability of a single oral dose of erdafitinib alone and when co-administered with steady state oral carbamazepine, a dual inducer of CYP3A4 and CYP2C9, in 13 healthy adult participants (NCT04330248). Compared with erdafitinib administration alone, carbamazepine co-administration decreased total and free maximum plasma concentrations of erdafitinib (Cmax) by 35% (95% CI 30%-39%) and 22% (95% CI 17%-27%), respectively. The areas under the concentration-time curve over the time interval from 0 to 168 hours, to the last quantifiable data point, and to time infinity (AUC168h, AUClast, AUCinf), were markedly decreased for both total erdafitinib (56%-62%) and free erdafitinib (48%-55%). The safety profile of erdafitinib was consistent with previous clinical studies in healthy participants, with no new safety concerns when administered with or without carbamazepine. Co-administration with carbamazepine may reduce the activity of erdafitinib due to reduced exposure. Concomitant use of strong CYP3A4 inducers with erdafitinib should be avoided.

A genetics-guided approach to the clinical management of schizophrenia

Schizophrenia is a highly heritable, severe mental illness characterized by hallucinations, delusions, social withdrawal, and cognitive dysfunction present in ∼1% of populations across cultures. There have been recent major advancements in our understanding of the genetic architecture of schizophrenia. Both rare, highly penetrant genetic variants as well as common, low-penetrant genetic variants can predispose individuals to schizophrenia and can impact the way people metabolize psychoactive medications used to treat schizophrenia. However, the impact of these findings on the clinical management of schizophrenia remains limited. This review highlights the few places where genetics currently informs schizophrenia management strategies, discusses major limitations, and reviews promising areas of genetics research that are most likely to impact future schizophrenia care. Specifically, I focuss on psychiatric genetic counseling, genetic testing strategies, pharmacogenetics, polygenic risk, and genetics-guided treatment. Lastly, I emphasize important ethical considerations in the clinical use of genetics for schizophrenia management, including the exacerbation of healthcare inequalities and unintended consequences of new genetic technologies.

Management of acute carbamazepine poisoning: A narrative review

Standard management protocols are lacking and specific antidotes are unavailable for acute carbamazepine (CBZ) poisoning. The objective of this review is to provide currently available information on acute CBZ poisoning, including its management, by describing and summarizing various therapeutic methods for its treatment according to previously published studies. Several treatment methods for CBZ poisoning will be briefly introduced, their advantages and disadvantages will be analyzed and compared, and suggestions for the clinical treatment of CBZ poisoning will be provided. A literature search was performed in various English and Chinese databases. In addition, the reference lists of identified articles were screened for additional relevant studies, including non-indexed reports. Non-peer-reviewed sources were also included. In the present review, 154 articles met the inclusion criteria including case reports, case series, descriptive cohorts, pharmacokinetic studies, and in vitro studies. Data on 67 patients, including 4 fatalities, were reviewed. Based on the summary of cases reported in the included articles, the cure rate of CBZ poisoning after symptomatic treatment was 82% and the efficiency of hemoperfusion was 58.2%. Based on the literature review, CBZ is moderately dialyzable and the recommendation for CBZ poisoning is supportive management and gastric lavage. In severe cases, extracorporeal treatment is recommended, with hemodialysis as the first choice.

In vitro comparative quality evaluation of different brands of carbamazepine tablets commercially available in Dessie town, Northeast Ethiopia

BACKGROUND

Good-quality drugs that fulfill the regulatory parameters and are produced per the current good manufacturing practice (cGMP) standards are very critical for the best therapeutic outcomes. However, the variety of branded drugs circulation in the market often put clinicians and pharmacists in a difficult situation of choice due to the possibility of interchangeability among brands, so we should ascertain the quality of the various brands of drugs, available in the drug market. The purpose of the study was to evaluate the quality and physicochemical equivalence of six brands of carbamazepine tablets that are commercially available in Dessie town, Northeast Ethiopia.

METHODS

An experimental study design was used. Six different brands of carbamazepine tablets were purchased from community pharmacies in Dessie town, Northeast Ethiopia, which were selected using simple random sampling methods. Identification, weight variation, friability, hardness, disintegration, dissolution test, and assay for the content of active ingredients were evaluated according to the procedures described in the United States Pharmacopeia (USP) and British Pharmacopeia (BP), and the results were compared with USP and BP standards. The difference (f1) and similarity (f2) factors were calculated to assess in vitro bioequivalence requirements.

RESULTS

The identification test results revealed that all samples contained the stated active pharmaceutical ingredients and all brands of carbamazepine tablets complied with the official specification for weight variation, friability, and hardness tests. The percentage concentration of carbamazepine was found in the range of 97.85 to 102.09, which met the USP specification of 92% to 108% of the stated amount. Similarly, all samples fulfilled disintegration time (i.e., ≤ 30 min) except brand CA1 (34.183 min) and dissolution tolerance limits (i.e., Q ≥ 75% at 60 min), which was found in the range of 91.673% -97.124%. The difference factor (f1) values were < 15 and the similarity factor (f2) values were > 50 for all the tested brands of carbamazepine tablets.

CONCLUSION

The present study revealed that all brands of carbamazepine 200 mg tablets met the quality control parameters as per pharmacopoeial specifications except the disintegration test of brand CA1, and could be used each brand interchangeably to achieve the desired therapeutic effect.

Induction of clastogenesis and gene mutations by carbamazepine (at its therapeutically effective serum levels) in mammalian cells and the dependence on human CYP2B6 enzyme activity

Carbamazepine (CBZ, an antiepileptic) is metabolized by multiple CYP enzymes to its epoxide and hydroxides; however, whether it is genotoxic remains unclear. In this study, molecular docking (CBZ to CYPs) and cytogenotoxic toxicity assays were employed to investigate the activation of CBZ for mutagenic effects, in various mammalian cell models. Docking results indicated that CBZ was valid as a substrate of human CYP2B6 and 2E1, while not for CYP1A1, 1A2, 1B1 or 3A4. In the Chinese hamster (V79) cell line and its derivatives genetically engineered for the expression of human CYP1A1, 1A2, 1B1, 2E1 or 3A4 CBZ (2.5 ~ 40 μM) did not induce micronucleus, while in human CYP2B6-expressing cells CBZ significantly induced micronucleus formation. In a human hepatoma C3A cell line, which endogenously expressed CYP2B6 twofold higher than in HepG2 cells, CBZ induced micronucleus potently, which was blocked by 1-aminobenzotriazole (inhibitor of CYPs) and ticlopidine (specific CYP2B6 inhibitor). In HepG2 cells CBZ did not induce micronucleus; however, pretreatment of the cells with CICTO (CYP2B6 inducer) led to micronucleus formation by CBZ, while rifampicin (CYP3A4 inducer) or PCB126 (CYP1A inducer) did not change the negative results. Immunofluorescent assay showed that CBZ selectively induced centromere-free micronucleus. Moreover, CBZ induced double-strand DNA breaks (γ-H2AX elevation, by Western blot) and PIG-A gene mutations (by flowcytometry) in C3A (threshold being 5 μM, lower than its therapeutic serum concentrations, 17 ~ 51 μM), with no effects in HepG2 cells. Clearly, CBZ may induce clastogenesis and gene mutations at its therapeutic concentrations, human CYP2B6 being a major activating enzyme.

Repurposing Carbamazepine To Treat Gonococcal Infection in Women: Oral Delivery for Control of Epilepsy Generates Therapeutically Effective Levels in Vaginal Secretions

Neisseria gonorrhoeae has developed resistance to all previous antibiotics used for treatment. This highlights a crucial need for novel antimicrobials to treat gonococcal infections. We previously showed that carbamazepine (Cz), one of the most commonly prescribed antiepileptic drugs, can block the interaction between gonococcal pili and the I-domain region of human complement receptor 3 (CR3)-an interaction that is vital for infection of the female cervix. We also show that Cz can completely clear an established N. gonorrhoeae infection of primary human cervical cells. In this study, we quantified Cz in serum, saliva, and vaginal fluid collected from 16 women who were, or were not, regularly taking Cz. We detected Cz in lower reproductive tract mucosal secretions in the test group (women taking Cz) at potentially therapeutic levels using a competitive ELISA. Furthermore, we found that Cz concentrations present in vaginal fluid from women taking this drug were sufficient to result in a greater than 99% reduction (within 24 h) in the number of viable gonococci recovered from ex vivo, human, primary cervical cell infections. These data provide strong support for the further development of Cz as a novel, host-targeted therapy to treat gonococcal cervicitis.

Uptake and Transport of Different Concentrations of PPCPs by Vegetables

In many parts of the world, water resources are scarce or even extremely scarce, and the reuse of water resources has become mainstream in today's world. Many regions use treated wastewater for agricultural irrigation, aquaculture, and other activities. However, in recent years, wastewater has been found to contain large amounts of pharmaceuticals and personal care products (PPCPs). Therefore, there is a potential risk of PPCPs being transported in the environment and affecting human health. In this study, we compared the uptake, transport, and accumulation of 27 PPCPs in three types of sprouts (radish, buckwheat, and okra).The bioaccumulation of amantadine, diphenhydramine, chlorpheniramine maleate, sibutramine, hemosibutramine, chlorosibutramine, N-monomethyl sibutramine, N, N-desmethyl sibutramine, and carbamazepine was found to be significantly higher in plants grown for 12 days in media containing 0.5, 5.0, and 50.0 ng/mL PPCPs. With increasing concentration of PPCPs in the culture solution, the amount of PPCPs absorbed by plants and the degree of accumulation also showed an increasing trend. At the same time, it was demonstrated that there was an obvious uptake transfer phenomenon of PPCPs by plants, and the trend of uptake transfer became more and more obvious as the concentration of external environmental pollutants increased. In addition, amantadine, chlorpheniramine maleate, carbamazepine, N, N-desmethyl sibutramine, hemosibutramine, and chlorosibutramine showed more active translocation in some plants (TF > 1.0).

Quercetin alleviates kainic acid-induced seizure by inhibiting the Nrf2-mediated ferroptosis pathway

BACKGROUND

Epilepsy is one of the most common neurological disorders in childhood. However, classical antiepileptic drugs are linked with drug toxicity and cognitive function impairment in children. Hence, it is essential to develop a novel therapy to solve this problem. Currently, studies indicate regulating the nuclear factor-erythroid 2-related factor 2 (Nrf2)-mediated ferroptosis pathway represents a potential advanced therapy for seizures. Hence, the present study aimed to explore whether quercetin, a natural polyphenol, could alleviate seizure-induced neuron death and preserve cognitive function by inhibiting Nrf2-mediated ferroptosis.

METHODS

Kainic acid-induced epileptic mice model, morris water maze (MWM) test, cell counting kit-8 (CCK-8) assays, western blotting analysis, enzyme-linked immunosorbent assay, flow cytometry, quantitative real-time reverse transcription PCR (qRT-PCR), immunofluorescence staining, and RNA sequencing analysis were employed to explore the potential mechanisms by which quercetin exerts protective effects on seizure-induced neuron death in kainic acid-induced epileptic mice model and glutamate-induced HT22 neuronal cell death.

RESULTS

Our findings suggested the association between the Nrf2-mediated ferroptosis pathway and seizures in a clinical setting. Quercetin pretreatment alleviates seizure-like behaviors and cognitive impairment in KA-induced epileptic mice. Additionally, in vitro, co-treatment with quercetin effectively exerts neuroprotective effects in glutamate-induced HT22 neuronal cell death. These protective effects were also closely linked to regulating the Nrf2-mediated ferroptosis pathway. Furthermore, bioinformatic profiling revealed that the SIRT1/Nrf2/SLC7A11/GPX4 pathway plays a crucial role in the Glu-induced HT22 cell death pretreated with quercetin.

CONCLUSIONS

These findings indicated that quercetin effectively protects against seizure-induced neuron death in vivo and in vitro and alleviates cognitive function impairment via the SIRT1/Nrf2/SLC7A11/GPX4 pathway.

Is the prevalence of thyroid disease higher in children receiving antiepileptic medication? A systematic review and meta-analysis

PURPOSE

Antiseizure medications (ASM) have long been examined for their potential to induce thyroid dysfunction. The aim of this systematic review and meta-analysis was to assess the prevalence of thyroid disease in children up to 16 years receiving monotherapy with valproate (VPA), carbamazepine (CBZ) and levetiracetam (LEV).

METHODS

PubMed/MEDLINE, Cochrane/CENTRAL databases and the gray literature were searched to identify observational studies providing the prevalence of thyroid dysfunction in the target population under VPA, CBZ, or LEV monotherapy schemes. The results were pooled using a random-effects model, and additional subgroup analyses were performed for the three ASM groups.

RESULTS

Fifteen and thirteen studies met inclusion criteria for the qualitative and the quantitative analysis, respectively, with a total of 945 pediatric patients with prevalence data. Only VPA and CBZ were associated with thyroid dysfunction. The overall prevalence of thyroid abnormality was higher in children receiving ASM [odds ratio (OR) 6.82, 95% confidence interval (CI) 3.96-11.75]. In the subgroup analysis, the prevalence of biochemical thyroid abnormality with increased TSH was higher in the VPA (OR 9.54, 95%CI 5.25-17.34) and the CBZ group (OR 4.08, 95%CI 1.84-9.04) compared with controls.

CONCLUSION

This study confirms the higher prevalence of biochemical thyroid abnormality in children under VPA and CBZ monotherapy, whereas no such evidence is present for LEV. In children with a predisposition for thyroid disease, LEV should be considered over VPA and CBZ, if appropriate for seizure type and epilepsy syndrome. More studies are needed to reach a consensus on monitoring and management of thyroid dysfunction in children receiving ASM therapy.

Influence of nanoparticle size on blood-brain barrier penetration and the accumulation of anti-seizure medicines in the brain

Anti-seizure medicines constitute a common yet important modality to treat epilepsy. However, some of them are associated with serious side effects including hepatotoxicity and hypersensitivity. Furthermore, the blood-brain barrier (BBB) is an insurmountable obstacle for brain drug delivery. Fortunately, the introduction of the nanoparticles for drug delivery is a feasible approach to overcome these obstacles. Encapsulating drugs into nanoparticles and delivering them to specific sites shows great potential for improving the efficiency of drug delivery and reducing systemic toxicity. Several in vivo studies have investigated the effect of nanoparticle size on biodistribution in mice, but very few have investigated its effects on efficient drug delivery while crossing the BBB. Therefore, we designed a methoxy poly(lactide-co-glycolide)-b-poly(ethylene glycol) methyl ether (mPEG-PLGA) nanoparticle delivery system and explored the cell uptake efficiency of nanoparticles with different sizes and their ability to penetrate the BBB while carrying carbamazepine (CBZ). CBZ-loaded nanoparticles could significantly reduce the cytotoxicity of CBZ to L929 cells at high concentrations. Results from the endocytosis experiment involving human cerebral microvessel endothelial cell/D3 showed that the DiR-loaded mPEG_5K-PLGA_10K nanoparticles possessed the highest cell uptake efficiency. The endocytosis efficiency was 90% at 30 min, which far exceeded that of the other groups. Moreover, similar results were obtained from subsequent experiments where fluorescence images of the isolated organs of the mice were acquired. To summarize, our study demonstrated that drug delivery to the brain using nanocarriers is size dependent. Nanoparticles with the smallest particle size can be internalized more effectively, and easily penetrate the BBB, and accumulate in the brain.

Carbamazepine Biosensor Development for Epilepsy Patient Screening

The San Carlos population in Chile is an example of an underserved community due to lack of timely access to regular controls and laboratory results. One particular challenge is the adherence to treatment of Epilepsy patients. In this work, we present the design and proof-of-concept of a Point of Care Device (POCD) to measure carbamazepine levels in saliva to screen for correct dose prescription among epilepsy patients. We present the Screen Printed Electrode design and activating circuit and preliminary results to verify feasibility of the biosensor. Future steps include the fabrication of the device itself and validation with the target population.

Carbamazepine Induces Platelet Apoptosis and Thrombocytopenia Through Protein Kinase A

Carbamazepine is extensively used worldwide to treat a wide range of disorders such as epilepsy, peripheral neuralgia and bipolar disorder. Thrombocytopenia and hemorrhage have been identified in multiple carbamazepine-treated patients. However, the underlying mechanism remains poorly understood. Here, we show that platelets undergo apoptosis after carbamazepine treatment. The apoptotic platelets induced by carbamazepine are rapidly removed in vivo, which accounts for thrombocytopenia. We found that carbamazepine treatment attenuates the phosphorylation level of bcl-xl/bcl-2-associated death promoter (BAD), vasodilator-associated stimulated phosphoprotein (VASP) and GPIbβ in platelets, indicating an inhibition effect on protein kinase A (PKA). We further demonstrated that carbamazepine reduced PKA activity through PI3K/Akt/PDE3A signaling pathway. Pharmacological activation of PKA or inhibition of PI3K/Akt/PDE3A protects platelets from apoptosis induced by carbamazepine. Importantly, PDE3A inhibitors or PKA activator ameliorates carbamazepine-mediated thrombocytopenia in vivo. These findings shed light on a possible mechanism of carbamazepine-induced thrombocytopenia, designating PDE3A/PKA as a potential therapeutic target in the treatment of carbamazepine-induced thrombocytopenia.

Carbamazepine drug reaction involving high fevers during the COVID-19 era

Carbamazepine has demonstrated anticonvulsant properties and is used for a variety of indications in psychiatry and neurology. Total daily doses typically range from 200 to 1200 mg/d, generally divided into 2 doses. Carbamazepine has a broad side-effect profile but is not typically thought to produce high fevers in the absence of a hypersensitivity syndrome. This is a case of a probable adverse drug reaction to carbamazepine consisting of fever without severe major organ involvement. In this instance, a patient in a manic episode with psychotic features was briefly transferred to a COVID-19 unit to rule out coronavirus infection before the fever resolved.

Potential Use of Pharmacogenetics to Reduce Drug-Induced Syndrome of Inappropriate Antidiuretic Hormone (SIADH)

Syndrome of inappropriate antidiuretic hormone (SIADH) is a common cause of hyponatremia, and many cases represent adverse reactions to drugs that alter ion channel conductance within the peptidergic nerve terminals of the posterior pituitary. The frequency of drug-induced SIADH increases with age; as many as 20% of patients residing in nursing homes have serum sodium levels below 135 mEq/L. Mild hyponatremia is associated with cognitive changes, gait instability, and falls. Severe hyponatremia is associated with cerebral edema, seizures, permanent disability, and/or death. Although pharmacogenetic tests are now being deployed for some drugs capable of causing SIADH (e.g., antidepressants, antipsychotics, and opioid analgesics), the implementation of these tests has been based upon the prior known association of these drugs with other serious adverse drug reactions (e.g., electrocardiographic abnormalities). Work is needed in large observational cohorts to quantify the strength of association between pharmacogene variants and drug-induced SIADH so that decision support can be developed to identify patients at high risk.

Determination of serum carbamazepine and its metabolite by validated tandem mass spectrometric method and the effect of carbamazepine on various hematological and biochemical parameters

OBJECTIVES

The study aimed to develop a validated LC-MS / MS method for the measurement of carbamazepine and carbamazepine-10,11-epoxide (CBZE) levels, to compare the carbamazepine concentrations measured by AbSciex API 3200 LC-MS/MS and Beckman Coulter Emit® 2000 immunoassay and to investigate the effect of carbamazepine concentrations on various hematological and biochemical parameters.

METHODS

For the measurement of carbamazepine and CBZE levels, a validated LC-MS / MS method was developed. Serum carbamazepine levels of patients were measured by AbSciex API 3200 LC-MS / MS and Beckman Coulter Emit® 2000 immunoassay. Biochemical, hematological parameters, and hormone levels were measured by Beckman-Coulter AU 5800 (Beckman Coulter, Brea, USA), Beckman Coulter LH 780 (Beckman Coulter, Miami, FL, USA), and Cobas 6000 (Roche Diagnostics, Germany) analyzers, respectively.

RESULTS

The imprecision values for all analytes were less than 7.0 %. The correlation coefficient between the methods was 0.981 (95 % confidence interval: 0.975 to 0.985). Linear regression analysis demonstrated highly significant associations of carbamazepine concentrations with albumin (B = -0.300, p = 0.040), calcium (B = -0.262, p = 0.004), phosphorus (B = -0.241, p = 0.022), WBC (B = -0.288, p = <0.001), PLT (B = -0.236, p = 0.003), RBC (B = -0.257, p = 0.001), NEU% (B = -0.289, p = <0.001), LYM% (B = -0.268, p = 0.001), D vitamini (B = -0.344, p = 0.006) levels.

CONCLUSIONS

A robust, rapid, and simple method has been developed. Our study revealed that carbamazepine and its metabolite have a significant correlation and likely impact on bone metabolism, blood cell counts, serum protein, albumin levels, and electrolyte concentrations.

Carbamazepine induced toxic epidermal necrolysis and Stevens-Johnson syndrome overlapping during pregnancy in a South-East Asian patient: A case report

Introduction

Toxic Epidermal Necrolysis (TEN) and Stevens-Johnson syndrome (SJS) are rare and severe forms of drug-induced skin reaction. Most frequently involved drugs are noted to be non-steroidal anti-inflammatory agents, antibiotics, and anticonvulsants. These have high morbidity and mortality and counts among dermatological emergencies.

Case presentation

We report an eventful case of a 22-year-old lady who suffered and recovered from carbamazepine-induced SJS/TEN overlapping during her pregnancy. Our patient had a history of epilepsy for which she was under sodium valproate. Switching to carbamazepine due to its low teratogenicity led our patient to this condition. History of prodromal symptoms and exposure to carbamazepine helped in the diagnosis. Carbamazepine abstinence and a multidisciplinary approach in symptomatic management worked very well for the patient.

Clinical discussion

Carbamazepine-induced TES/SJS manifests multisystem effects and requires a multidisciplinary approach for management. The condition itself is life-threatening and in its addition, their sequelae further threaten the life of the patients. Early intervention is the key. Genetically susceptible are thought to be the ones carrying human leukocyte antigen B*15:02 (HLA-B*15:02) allele and it is most prevalent in South-East Asian populations. Screening of this allele before using carbamazepine prevents the incidence of carbamazepine-induced SJS/TEN.

Conclusion

Prodromal symptoms of carbamazepine-induced SJS/TEN constitute flu-like symptoms that should not be missed. Early intervention and multidisciplinary approach prevent secondary infections and complications. Screening for HLA-B*15:02 variant allele and close monitoring of these adverse reactions along with proper counseling to patients goes a long way in preventing the development of this life-threatening condition.

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Carbamazepine-induced cutaneous reaction may present as Stevens-Johnson Syndrome (SJS) or toxic epidermal necrolysis (TEN).

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Carriers of the human leukocyte antigen B*1502 gene are susceptible to developing carbamazepine-induced SJS/TEN.

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Human leukocyte antigen B*1502 gene is most prevalent in South-East Asia.

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SJS/TEN affect multisystem and need a multidisciplinary approach in management.

Oxcarbazepine for Behavioral Disorders after Brain Injury: Factors Influencing Efficacy

Carbamazepine and oxcarbazepine are used for behavioral disorders following organic diseases. After severe acquired brain injury, patients may develop frontal symptoms. In our neurological rehabilitation routine, oxcarbazepine is used for better safety over carbamazepine, although its efficacy is not clarified. We aimed to improve knowledge on this use of oxcarbazepine, by probing clinical factors associated with response. We retrospectively examined the clinical records of our patients, collecting clinical variables and outcomes of efficacy, both clinician-rated and caregiver/self-rated. We described the distribution of clinical variables and examined their associations via logistic regressions. Patients in our cohort were predominantly pediatric, with frontal lobe damage and irritable/reactive. With an oxcarbazepine median dose of 975 mg, almost half of patients improved. We found several clinical factors associated with clinician-rated efficacy: absence of frontal damage and absence of irritability/reactivity symptoms; clinical factors associated with caregivers/patients-rated efficacy were: higher DRS score at baseline and higher patient age. In this retrospective study, we observed that oxcarbazepine was differentially efficacious in patients with specific characteristics. Our study could not examine drug therapy separately from neuropsychological therapy, nor the influence of dose. Our associative results should be verified experimentally, also assessing causality and establishing dose-related efficacy and safety.

Carbamazepine Reduces Sharp Wave-Ripple Complexes and Exerts Synapse-Specific Inhibition of Neurotransmission in Ex Vivo Hippocampal Slices

Higher therapeutic concentrations of the antiseizure medication carbamazepine (CBZ) are associated with cognitive side effects. Hippocampal sharp wave-ripple complexes (SPW-Rs) are proposed to participate in memory consolidation during periods of quiet and slow-wave sleep. SPW-Rs are generated in the CA3 region and are regulated by multiple synaptic inputs. Here, we used a multi-electrode array to determine the effects of CBZ on SPW-Rs and synaptic transmission at multiple hippocampal synapses. Our results demonstrate that CBZ reduced SPW-Rs at therapeutically relevant concentrations (IC₅₀ = 37 μM) and altered the core characteristics of ripples, important for information processing and consolidation. Moreover, CBZ inhibited neurotransmission in a synapse-specific manner. CBZ inhibition was most potent at the medial-perforant-path-to-CA3 and mossy-fiber-to-CA3 synapses (IC₅₀s ~ 30 and 60 μM, respectively) and least potent at medial-perforant-path-to-dentate granule cell synapses (IC₅₀ ~ 120 μM). These results suggest that the synapse-specific CBZ inhibition of neurotransmission reduces SPW-Rs and that the CBZ inhibition of SPW-Rs may underlie the cognitive impairments observed with therapeutic doses of CBZ.

Carbamazepine induces hepatotoxicity in zebrafish by inhibition of the Wnt/β-catenin signaling pathway

As drug abuse has become increasingly serious, carbamazepine (CBZ) is discharged into the aquatic environment with municipal sewage, causing potential harm to aquatic organisms. Here, we utilized zebrafish, an aquatic vertebrate model, to comprehensively evaluate the hepatotoxicity of CBZ. The larvae were exposed to 0.07, 0.13, and 0.26 mmol/L CBZ from 72 hpf to 144 hpf, and the adults were exposed to 0.025, 0.05, and 0.1 mmol/L CBZ for 28 days. The substantial changes were observed in the size and histopathology of livers, indicating that CBZ induced severe hepatoxicity in the larvae and adults. Oil red O staining demonstrated CBZ exposure caused severe lipid accumulation in the livers of both larvae and adults. Furthermore, CBZ exposure facilitated hepatocyte apoptosis through TUNEL staining, which was caused by rising ROS content. Subsequently, down-regulation of genes related to the Wnt pathway in exposure groups indicated that CBZ inhibited the development of liver via the Wnt/β-catenin signaling pathway. In conclusion, CBZ induced severe hepatotoxicity by promoting lipid accumulation, generating excessive ROS production, and inhibiting the Wnt/β-catenin signaling pathway in zebrafish. The results reveal the occurrence of CBZ-induced hepatotoxicity in zebrafish and clarify its mechanism of action, which potentially illustrate environmental concerns associated with CBZ exposure.

Effect of Chronic Administration of 5-(3-chlorophenyl)-4-Hexyl-2,4 -Dihydro-3H-1,2,4-Triazole-3-Thione (TP-315)-A New Anticonvulsant Drug Candidate-On Living Organisms

About 70 million people suffer from epilepsy—a chronic neurodegenerative disease. In most cases, the cause of the disease is unknown, but epilepsy can also develop as the result of a stroke, trauma to the brain, or the use of psychotropic substances. The treatment of epilepsy is mainly based on the administration of anticonvulsants, which the patient must most often use throughout their life. Despite significant progress in research on antiepileptic drugs, about 30% of patients still have drug-resistant epilepsy, which is insensitive to pharmacotherapy used so far. In our recent studies, we have shown that 4-alkyl-5-aryl-1,2,4-triazole-3-thiones act on the voltage-gated sodium channels and exhibit anticonvulsant activity in an MES (maximal electroshock-induced seizure) and 6Hz test in mice. Previous studies have shown their beneficial toxic and pharmacological profile, but their effect on a living organism during chronic use is still unknown. In the presented study, on the basis of the previously conducted tests and the PAMPA (parallel artificial membrane permeability assay) BBB (blood–brain barrier) test, we selected one 1,2,4-triazole-3-thione derivative—TP-315—for further studies aimed at assessing the impact of its chronic use on a living organism. After long-term administration of TP-315 to Albino Swiss mice, its effect on the functional parameters of internal organs was assessed by performing biochemical, morphological, and histopathological examinations. It was also determined whether the tested compound inhibits selected isoforms of the CYP450 enzyme system. On the basis of the conducted tests, it was found that TP-315 does not show nephrotoxic nor hepatotoxic effects and does not cause changes in hematological parameters. In vitro tests showed that TP-315 did not inhibit CYP2B6, CYP2D6, CYP3A4, or CYP3A5 enzymes at the concentration found in the serum of mice subjected to long-term exposure to this compound.

Environmentally relevant concentrations of carbamazepine induced lipid metabolism disorder of Chinese rare minnow (Gobiocypris rarus) in a gender-specific pattern

Carbamazepine (CBZ), an anticonvulsant and mood stabilizer, is ubiquitous distributed in aquatic environment. Though the toxicity and endocrine disrupting effect of CBZ on non-target organisms have been studied, its lipotoxity are scarcely known. To assess the lipotoxicity of CBZ, 2-month-old Chinese rare minnow were exposed to 0, 1, 10, and 100 μg/L CBZ for 90 d. Obvious dyslipidemia was observed after 30 d and 90 d exposure, whereas overt hyperlipidemia was observed in males at 100 μg/L treatments. Severe lipid droplet accumulation in livers was observed at 10 and 100 μg/L treatments for 30 d and in females, whereas those was observed at all treatments in males. In addition, serious mitochondria damage was observed in males at 100 μg/L treatments. After 90 d exposure, the enzyme activities of FAS and ACCα were significantly increased at 10 and 100 μg/L treatments, whereas HMGCR were markedly increased at 100 μg/L treatments (p < 0.05). However, ACCβ were markedly decreased in females at 10 and 100 μg/L treatments and in males at all treatments (p < 0.05). The transcription levels of fasn, accα, hmgcrα, fdft1, idi1, plin1, plin2, caveolin1, and caveolin2 were significantly increased at 100 μg/L treatments (p < 0.05). Moreover, the body weight was obviously increased at 10 and 100 μg/L treatments in males (p < 0.05). Our results confirmed that environmental relevant concentrations CBZ induced lipid metabolism disorder and mitochondria damage of Chinese rare minnow in a gender-specific pattern, which provided a new insight into the lipotoxicity mechanism of CBZ.

Toxicological outcome of exposure to psychoactive drugs carbamazepine and diazepam on non-target insect Nauphoeta cinerea

The continuous detection of human pharmaceuticals during environmental biomonitoring is a global concern because of the menaces they may exert on non-target organisms. Carbamazepine (CBZ) and diazepam (DZP) are commonly prescribed psychotropic drugs which have been reported to coexist in the environment globally. Nauphoeta cinerea is a common insect with high ecological impact. This study elucidated the influence of co-exposure to DZP (0.5 and 1.0 μg kg^-1 diet) and CBZ (1.5 and 3.0 μg kg^-1 diet) for 42 days on the behavior and biochemical responses in Nauphoeta cinerea. Results showed that DZP alone did not induce adverse effect on the behavior and antioxidant status in the exposed insects. However, exposure to CBZ alone and binary mixtures of DZP and CBZ significantly decreased locomotor and exploratory accomplishments evidenced by decreased mobile episodes, total mobile time, maximum speed, total distance traveled, absolute turn angle, body rotation and path efficiency in comparison with control. The decline observed in the exploratory activities of insects fed with CBZ alone and the mixtures was confirmed by track plots and heat maps. Further, acetylcholinesterase and antioxidant enzyme activities decreased significantly whereas reactive oxygen and nitrogen species, nitric oxide and lipid peroxidation levels increased significantly in the hemolymph, head and midgut of insects exposed to CBZ alone and the mixtures. Collectively, CBZ alone and binary mixtures of CBZ and DZP caused neurotoxicity via induction of inflammatory and oxidative stress in insects. Nauphoeta cinerea may be a potential non-target insect model for monitoring ecotoxicological hazard of pharmaceuticals.

Presence of allele CYP3A4*16 does not have any bearing on carbamazepine-induced adverse drug reactions in North Indian people with epilepsy

OBJECTIVES:

The objectives of this study were to determine the relationship between genetic polymorphisms in gene encodings for CYP3A4 and carbamazepine (CBZ)-induced dose-related side effects in North Indian people with epilepsy.

PATIENTS AND METHODS:

The current prospective study included 37 patients with CBZ-induced dose-related side effects and 102 patients who did not experience side effects while on CBZ. The genotyping for CYP3A4 allele (CYP3A4*16) was done using real-time polymerase chain reaction (RT-PCR) in Applied Biosystems 7500 RT-PCR System (USA). CBZ was administered in all patients at a dose varying from 15 to 20 mg/kg daily.

RESULTS:

Various demographic variables were comparable between the groups except that control of seizures was far better in controls. After testing, it was found that none of our patients had the presence of CYP3A4*16 allele.

CONCLUSION:

CYP3A4*16 allele is not represented significantly in North Indian people with CBZ-induced dose-related side effects.

How Can Drug Metabolism and Transporter Genetics Inform Psychotropic Prescribing?

Many genetic variants in drug metabolizing enzymes and transporters have been shown to be relevant for treating psychiatric disorders. Associations are strong enough to feature on drug labels and for prescribing guidelines based on such data. A range of commercial tests are available; however, there is variability in included genetic variants, methodology, and interpretation. We herein provide relevant background for understanding clinical associations with specific variants, other factors that are relevant to consider when interpreting such data (such as age, gender, drug-drug interactions), and summarize the data relevant to clinical utility of pharmacogenetic testing in psychiatry and the available prescribing guidelines. We also highlight areas for future research focus in this field.

Pharmacogenomic Biomarkers and Their Applications in Psychiatry

Realizing the promise of precision medicine in psychiatry is a laudable and beneficial endeavor, since it should markedly reduce morbidity and mortality and, in effect, alleviate the economic and social burden of psychiatric disorders. This review aims to summarize important issues on pharmacogenomics in psychiatry that have laid the foundation towards personalized pharmacotherapy and, in a broader sense, precision medicine. We present major pharmacogenomic biomarkers and their applications in a variety of psychiatric disorders, such as depression, attention-deficit/hyperactivity disorder (ADHD), narcolepsy, schizophrenia, and bipolar disorder. In addition, we extend the scope into epilepsy, since antiepileptic drugs are widely used to treat psychiatric disorders, although epilepsy is conventionally considered to be a neurological disorder.

Lithium for Carbamazepine-Induced Syndrome of Inappropriate Antidiuretic Hormone

OBJECTIVES

To examine the effectiveness of low-dose lithium carbonate for managing carbamazepine-induced hyponatremia.

METHODS

Single case study in an 88 year old man with bipolar illness and vascular dementia who had failed to respond to other mood stabilizers.

RESULTS

The patient had developed hyponatremia on two separate occasions when treated with carbamazepine. Introduction of low-dose lithium resulted in prompt normalization of serum sodium levels, which was maintained for the subsequent 8 weeks.

CONCLUSIONS

Carbamazepine may sometimes be the best or only viable treatment option for patients with bipolar illness or other conditions. When its use is complicated by syndrome of inappropriate ADH, dose reduction and fluid restriction are the simplest options but, if ineffective, addition of lithium may be a feasible, albeit somewhat complicated, alternative.

Carbamazepine induces a bioenergetics disruption to microvascular endothelial cells from the blood-brain barrier

Carbamazepine (CBZ) is a widely employed anti-seizure medication that crosses the blood-brain barrier (BBB) to exert its anti-convulsant action. The effects of CBZ on components of the BBB have yet to be completely delineated. Hence the current study evaluated the effects of CBZ upon mitochondrial functionality of BBB-derived microvascular endothelial cells isolated from Albino rats. The influence of CBZ on cell viability and barrier functions were evaluated by 3-(4,5 dimethylthiazol-2-yl)-2,5-diphenyl-tetrazolium bromide (MTT), lactate dehydrogenase, and electrophysiological assays over a drug concentration range of 0.1-1000 μM. Bioenergetics effects were measured via ATP production, mitochondrial complexes I and III activities, lactate production, and oxygen consumption rates (OCRs), and mitochondrial membrane potential, fluidity and lipid content. CBZ was cytotoxic to microvascular endothelial cells in a concentration and duration dependent manner. CBZ significantly diminished the endothelial cell's barrier functions, and impacted upon cellular bioenergetics: reducing mitochondrial complex activities with a parallel decrease in OCRs and increased anaerobic lactate production. CBZ significantly decreased mitochondrial membrane potential and induced an increase of membrane fluidity and decrease in levels of mitochondrial saturated and unsaturated fatty acids. In summary, CBZ disrupted functional activity of BBB endothelial cells via damage and modification of mitochondria functionality at therapeutically relevant concentrations.

All about pain pharmacology: what pain physicians should know

From the perspective of the definition of pain, pain can be divided into emotional and sensory components, which originate from potential and actual tissue damage, respectively. The pharmacologic treatment of the emotional pain component includes antianxiety drugs, antidepressants, and antipsychotics. The anti-anxiety drugs have anti-anxious, sedative, and somnolent effects. The antipsychotics are effective in patients with positive symptoms of psychosis. On the other hand, the sensory pain component can be divided into nociceptive and neuropathic pain. Non-steroidal anti-inflammatory drugs (NSAIDs) and opioids are usually applied for somatic and visceral nociceptive pain, respectively; anticonvulsants and antidepressants are administered for the treatment of neuropathic pain with positive and negative symptoms, respectively. The NSAIDs, which inhibit the cyclo-oxygenase pathway, exhibit anti-inflammatory, antipyretic, and analgesic effects; however, they have a therapeutic ceiling. The adverse reactions (ADRs) of the NSAIDs include gastrointestinal problems, generalized edema, and increased bleeding tendency. The opioids, which bind to the opioid receptors, present an analgesic effect only, without anti-inflammatory, antipyretic, or ceiling effects. The ADRs of the opioids start from itching and nausea/vomiting to cardiovascular and respiratory depression, as well as constipation. The anticonvulsants include carbamazepine, related to sodium channel blockade, and gabapentin and pregabalin, related to calcium blockade. The antidepressants show their analgesic actions mainly through inhibiting the reuptake of serotonin or norepinephrine. Most drugs, except NSAIDs, need an up-dose titration period. The principle of polypharmacy for analgesia in case of mixed components of pain is increasing therapeutic effects while reducing ADRs, based on the origin of the pain.

An Update on the Immunological, Metabolic and Genetic Mechanisms in Drug Hypersensitivity Reactions

Drug hypersensitivity reactions (DHRs) represent a major burden on the healthcare system since their diagnostic and management are complex. As they can be influenced by individual genetic background, it is conceivable that the identification of variants in genes potentially involved could be used in genetic testing for the prevention of adverse effects during drug administration. Most genetic studies on severe DHRs have documented HLA alleles as risk factors and some mechanistic models support these associations, which try to shed light on the interaction between drugs and the immune system during lymphocyte presentation. In this sense, drugs are small molecules that behave as haptens, and currently three hypotheses try to explain how they interact with the immune system to induce DHRs: the hapten hypothesis, the direct pharmacological interaction of drugs with immune receptors hypothesis (p-i concept), and the altered self-peptide repertoire hypothesis. The interaction will depend on the nature of the drug and its reactivity, the metabolites generated and the specific HLA alleles. However, there is still a need of a better understanding of the different aspects related to the immunological mechanism, the drug determinants that are finally presented as well as the genetic factors for increasing the risk of suffering DHRs. Most available information on the predictive capacity of genetic testing refers to abacavir hypersensitivity and anticonvulsants-induced severe cutaneous reactions. Better understanding of the underlying mechanisms of DHRs will help us to identify the drugs likely to induce DHRs and to manage patients at risk.

Development of a rapid and reliable single-tube multiplex real-time PCR method for HLA-A*24:02 genotyping

Aim: HLA-A*24:02 is significantly associated with cutaneous adverse drug reactions caused by aromatic antiepileptic drugs. Here, we aimed to establish a fast and reliable detection method for HLA-A*24:02 genotyping. Methods: A single-tube multiplex quantitative real-time polymerase chain reaction (qPCR) assay for HLA-A*24:02 genotyping was established by combining allele-specific primers with TaqMan probes. Results: A 100% concordance was observed between qPCR and SBT result in 106 Han subjects. The detection limit of the new method was 0.05 ng DNA. The positive rate of HLA-A*24:02 in Tibetans (55.6%, n = 81) was significantly higher than those in Han (34%, n = 106), Uighur (27.5%, n = 102), Bouyei (25.9%, n = 116) and Miao populations (26.5%, n = 113). Conclusion: The newly established qPCR assay was reliable for HLA-A*24:02 screening in clinical applications.

Research Progress on the Animal Models of Drug-Induced Liver Injury: Current Status and Further Perspectives

Drug-induced liver injury (DILI) is a major concern in clinical studies as well as in postmarketing surveillance. It is necessary to establish an animal model of DILI for thorough investigation of mechanisms of DILI and searching for protective medications. This article reviews the current status and future perspective on establishment of DILI models based on different hepatotoxic drugs, as well as the underlying mechanisms of liver function damage induced by specific medicine. Therefore, information from this article can help researchers make a suitable selection of animal models for further study.

A genome-wide association study of sodium levels and drug metabolism in an epilepsy cohort treated with carbamazepine and oxcarbazepine

OBJECTIVE

To ascertain the clinical and genetic factors contributing to carbamazepine- and oxcarbazepine-induced hyponatremia (COIH), and to carbamazepine (CBZ) metabolism, in a retrospectively collected, cross-sectional cohort of people with epilepsy.

METHODS

We collected data on serum sodium levels and antiepileptic drug levels in people with epilepsy attending a tertiary epilepsy center while on treatment with CBZ or OXC. We defined hyponatremia as Na+ ≤134 mEq/L. We estimated the CBZ metabolic ratio defined as the log transformation of the ratio of metabolite CBZ-diol to unchanged drug precursor substrate as measured in serum.

RESULTS

Clinical and genetic data relating to carbamazepine and oxcarbazepine trials were collected in 1141 patients. We did not observe any genome-wide significant associations with sodium level in a linear trend or hyponatremia as a dichotomous trait. Age, sex, number of comedications, phenytoin use, phenobarbital use, and sodium valproate use were significant predictors of CBZ metabolic ratio. No genome-wide significant associations with CBZ metabolic ratio were found.

SIGNIFICANCE

Although we did not detect a genetic predictor of hyponatremia or CBZ metabolism in our cohort, our findings suggest that the determinants of CBZ metabolism are multifactorial.

An Interesting Case of Carbamazepine-Induced Stevens-Johnson Syndrome

A 29-year-old Black female patient was admitted to a psychiatric ward with symptoms of major depressive disorder with psychosis. The patient was started on amitriptyline 50 mg/day and haloperidol 10 mg/day. On day 4 post-admission, the preferred first-line antidepressant, fluoxetine, became available and the patient was switched from amitriptyline to fluoxetine 20 mg/day. On the same day, the dose of haloperidol was reduced to 5 mg/day. Thirteen days post-initiation of these medications the patient became talkative, associated with emotional lability, an expansive mood, irritability and restlessness. The working diagnosis was changed to bipolar affective disorder in the manic phase. Fluoxetine was discontinued and carbamazepine 600 mg/day was added to the patient's treatment regimen. Her manic symptoms started to resolve; however, 14 days post-initiation of carbamazepine, the patient had a fever; itchy, discharging eyes; respiratory distress; generalised symmetrical erythematosus rash; buccal ulceration; and conjunctival injection with difficulty opening her eyes. Carbamazepine was immediately discontinued and the patient received intravenous fluid resuscitation. The patient recovered considerably after 12 days of symptomatic and supportive management, and was transferred back to the psychiatric ward for the continuation of bipolar disorder management. Lithium therapy was instituted and the patient was subsequently discharged. Using the Algorithm of Drug causality for Epidermal Necrolysis (ALDEN) Stevens-Johnson Syndrome/toxic epidermal necrolysis (SJS/TEN) drug causality scoring system, carbamazepine and fluoxetine were evaluated as 'very probable' and 'possible' causes of SJS, respectively, in this patient. Fluoxetine-induced SJS was considered on account of previous case reports, however no evidence of causality was found in this patient. Consecutive administration with a potential increase in carbamazepine due to inhibition of cytochrome P450 (CYP) 3A4 metabolism by fluoxetine was also not ruled out. A diagnosis of carbamazepine-induced SJS was made and was considered an idiosyncratic adverse drug reaction.