Trends in Tramadol

Skills and practices of pharmacy staff for dispensing of drugs with fiscalized substances in drugstores and pharmacies

OBJETIVE

To evaluate the skills and practices of pharmacy staff during the dispensing of tramadol (drug with fiscalized substance) in drugstores and pharmacies in Medellin, Colombia.

METHODS

A cross-sectional study was performed. The simulated patient technique was used. The main outcomes included the information provided on the dispensed drug (tramadol), the use of tools to provide information, and the information provided on drug precautions and use recommendations.

RESULTS

We visited 305 drugstores and pharmacies. The average dispensing time was 2.3 min (SD 1.1 min). In nine drugstores and pharmacies (3.0%), tramadol was not dispensed because it was not in stock. In 17 drugstores and pharmacies (5.7%), the simulated patients were actively informed by the dispensing pharmacy staff; of these, 16 provided oral information and one provided oral and written information. Eight patients (2.7%) received information regarding tramadol use. However, 99% of patients were not informed about tramadol side effects such as dependence, sedation, or hypnosis, and none of the simulated female patients were informed on the precautions related to tramadol use during pregnancy or lactation.

CONCLUSIONS

Communication skills and appropriate practices of pharmacy staff are critical to patient self-care. However, this study shows their difficulty in counseling about precautions and use recommendations of drugs with fiscalized substances. These outcomes could inform future studies focusing on the rational use of these drugs in drugstores and pharmacies. It is necessary to improve the pharmacy staff competencies through continuing education programs, to facilitate access to information and training.

Acute Pain Crisis Caused by Tramadol Remdesivir Drug-Drug Interaction

Drug interactions are common and can affect patient outcomes. Drugs that undergo emergency approval have less preapproval drug testing to identify potential interactions. Tramadol is an effective pain medication prodrug with a complex mechanism of action that requires extensive metabolism. Remdesivir is an antiviral medication given emergency approval to treat hospitalized patients with COVID-19 infections. Remdesivir is also a nucleotide analogue prodrug that undergoes intracellular metabolic conversions to its active metabolite. We discuss the case of a hospitalized patient in the United States diagnosed with COVID-19 pneumonia who developed acute pain crisis secondary to a drug-drug interaction between tramadol and remdesivir, and we propose a possible mechanism of interaction.

ANALGESIC EFFECT OF TRAMADOL IS NOT ALTERED BY POSTOPERATIVE SYSTEMIC INFLAMMATION AFTER MAJOR ABDOMINAL SURGERY

Tramadol is a commonly used analgesic in intensive care units (ICUs) for acute postoperative pain. Conversion of tramadol into active metabolites may be impaired in inflammatory states. Catechol-O-methyltransferase may influence pain. The aim of the study was to examine differences in the analgesic effect of tramadol between ICU patients with and without signs of systemic inflammation. Forty-three patients were admitted to ICU after a major abdominal surgery. The patients received a dose of 100 mg of tramadol intravenously every 6 hours during the first 24 hours after surgical procedure. Pain scores were measured by the Numeric Rating Scale before and 30 minutes after tramadol administration in awake patients. Systemic inflammation was considered when at least two of the following postoperative parameters were present in the first 24 hours of ICU admission: fever or hypothermia, tachycardia, pCO₂ <4.3 kPa, white blood cells >12000/mm³ or <4000/mm³, or preoperative value of C-reactive protein (CRP) >50 mg/L or/and procalcitonin (PCT) >0.5 mg/L. Catechol-O-methyltransferase was analyzed postoperatively. Fifteen (34.8%) patients met the criteria for systemic inflammation. Tramadol was proven to be an effective analgesic for the treatment of postoperative pain regardless of the presence of systemic inflammation (p<0.05). Lower perception of pain before tramadol application was observed in patients with systemic inflammation, but the difference was not significant. A negative correlation was observed between the preoperative values of CRP and PCT and the analgesic effect of tramadol assessed at the second measurement point (r=-0.358, p=0.03, and r=-0.364, p=0.02, respectively). Catechol-O-methyltransferase variants were not in correlation with pain and opioid consumption. Based on our findings, tramadol is effective in lowering pain scores after major abdominal surgery irrespective of the presence of systemic inflammation.

Unrecognized Postoperative Opioid-Induced Movement Disorder: A Case Report

A 22-year-old man, with a medical history significant for posttraumatic stress disorder and chronic pain, underwent ankle surgery at the United States Naval Hospital, Yokosuka, Japan. His immediate postoperative course was complicated by episodic muscle rigidity, necessitating admission for diagnostic evaluation. The differential was necessarily broad and included local anesthetic toxicity, medication mediated effect, seizures, serotonin syndrome, and malignant hyperthermia. Cultural and systemic differences in patient care delivery at a Japanese hospital helped to elucidate the mechanism. This case highlights cultural differences in pain management and navigates the differential of an acute onset movement disorder in the immediate postoperative period.

Different Pharmacokinetics of Tramadol, O-Demethyltramadol and N-Demethyltramadol in Postoperative Surgical Patients From Those Observed in Medical Patients

Background: Most studies examining tramadol metabolism have been carried out in non-surgical patients and with oral tramadol. The aim of this study was 1) to measure concentrations of tramadol, O-demethyltramadol (ODT), and N-demethyltramadol (NDT) in the surgical patients admitted to the intensive care unit (ICU) within the first 24 postoperative hours after intravenous application of tramadol, and 2) to examine the effect of systemic inflammation on tramadol metabolism and postoperative pain. Methods: A prospective observational study was carried out in the surgical ICU in the tertiary hospital. In the group of 47 subsequent patients undergoing major abdominal surgery, pre-operative blood samples were taken for CYP2D6 polymorphism analysis. Systemic inflammation was assessed based on laboratory and clinical indicators. All patients received 100 mg of tramadol intravenously every 6 h during the first postoperative day. Postoperative pain was assessed before and 30 min after tramadol injections. Tramadol, ODT, and NDT concentrations were determined by high-performance liquid chromatography. Results: CYP2D6 analysis revealed 2 poor (PM), 22 intermediate (IM), 22 extensive (EM), and 1 ultrafast metabolizer. After a dose of 100 mg of tramadol, t1/2 of 4.8 (3.2-7.6) h was observed. There were no differences in tramadol concentration among metabolic phenotypes. The area under the concentration-time curve at the first dose interval (AUC1-6) of tramadol was 1,200 (917.9-1944.4) μg ×h ×L-1. NDT concentrations in UM were below the limit of quantification until the second dose of tramadol was administrated, while PM had higher NDT concentrations compared to EM and IM. ODT concentrations were higher in EM, compared to IM and PM. ODT AUC1-6 was 229.6 (137.7-326.2) μg ×h ×L-1 and 95.5 (49.1-204.3) μg ×h ×L-1 in EM and IM, respectively (p = 0.004). Preoperative cholinesterase activity (ChE) of ≤4244 U L-1 was a cut-off value for a prediction of systemic inflammation in an early postoperative period. NDT AUC1-6 were significantly higher in patients with low ChE compared with normal ChE patients (p = 0.006). Pain measurements have confirmed that sufficient pain control was achieved in all patients after the second tramadol dose, except in the PM. Conclusions: CYP2D6 polymorphism is a major factor in O-demethylation, while systemic inflammation accompanied by low ChE has an important role in the N-demethylation of tramadol in postoperative patients. Concentrations of tramadol, ODT, and NDT are lower in surgical patients than previously reported in non-surgical patients. Clinical Trial Registration: ClinicalTrials.gov, NCT04004481.

Traces of tramadol in water impact behaviour in a native European fish

Tramadol is a widely used analgesic with additional antidepressant and anxiolytic effects. This compound has been reported in continental waters reaching concentrations of µg/L as a consequence of its inefficient removal in sewage treatment plants and increasing use over time. In this study, European chubs (Squalius cephalus) were exposed to 1 µg/L of tramadol in water for 42 days with a subsequent 14 days of depuration. Our results revealed that chubs exposed to this analgesic underwent changes in their behaviour as compared to the control group. The behavioural outcome was also influenced by the individual concentration of tramadol in brain tissue. In particular, experimental fish presented anxiolytic-like effects, characterized by less bold and less social individuals. Exposed animals were less frequently out of the shelter and moved a shorter distance, indicating that they explored the new environment less during the boldness test. In the novel object recognition experiment, although they distinguished the new item, they examined it less and displayed a reduced activity. Shoal cohesion was disrupted as observed in an increased distance between individuals. After the depuration phase, this alteration remained whereas the boldness effect disappeared. Moreover, the degree of behavioural changes was correlated with the concentration of the substance in brain. According to our findings, chronic presence of tramadol in the environment can impact the fitness of exposed aquatic fauna by altering evolutionary crucial behaviours.

Metabolic N-Dealkylation and N-Oxidation as Elucidators of the Role of Alkylamino Moieties in Drugs Acting at Various Receptors

Metabolic reactions that occur at alkylamino moieties may provide insight into the roles of these moieties when they are parts of drug molecules that act at different receptors. N-dealkylation of N,N-dialkylamino moieties has been associated with retaining, attenuation or loss of pharmacologic activities of metabolites compared to their parent drugs. Further, N-dealkylation has resulted in clinically used drugs, activation of prodrugs, change of receptor selectivity, and providing potential for developing fully-fledged drugs. While both secondary and tertiary alkylamino moieties (open chain aliphatic or heterocyclic) are metabolized by CYP450 isozymes oxidative N-dealkylation, only tertiary alkylamino moieties are subject to metabolic N-oxidation by Flavin-containing monooxygenase (FMO) to give N-oxide products. In this review, two aspects will be examined after surveying the metabolism of representative alkylamino-moieties-containing drugs that act at various receptors (i) the pharmacologic activities and relevant physicochemical properties (basicity and polarity) of the metabolites with respect to their parent drugs and (ii) the role of alkylamino moieties on the molecular docking of drugs in receptors. Such information is illuminative in structure-based drug design considering that fully-fledged metabolite drugs and metabolite prodrugs have been, respectively, developed from N-desalkyl and N-oxide metabolites.

Acetaminophen and tramadol hydrochloride-loaded soft gelatin capsule: preparation, dissolution and pharmacokinetics in beagle dogs

The objective of this study was to develop a novel acetaminophen and tramadol hydrochloride-loaded soft capsule (ATSC) with enhanced bioavailability of tramadol. The ATSC was manufactured in a pilot-scale batch size with the capsule contents composed of tramadol, acetaminophen, PEG 400 and Capmul MCM at a weight ratio of 37.5:325:177.5:30. Moreover, its dissolution, stability and pharmacokinetics in beagle dogs were carried out compared to commercial tablet. The dissolved amounts of acetaminophen from the ATSC and commercial tablet were not significantly different. However, compared to the latter, the former had significantly higher dissolution rate of tramadol at the initial times. In beagle dogs, the ATSC provided no significant difference in plasma concentrations and AUC of acetaminophen than did the commercial tablet; however, it significantly improved those of tramadol compared to the other, indicating the enhanced oral bioavailability of tramadol. Compared to the commercial tablet, the ATSC had a larger AUC value for tramadol (55.27 ± 11.06 vs. 92.62 ± 21.52 h·ng/ml). In the accelerated long-term stability, the ATSC offered higher than 96% drug content of acetaminophen and tramadol, suggesting that it was stable for at least six months. Therefore, this ATSC would be a recommendable candidate with enhanced oral bioavailability and excellent stability.

A review on tramadol toxicity: mechanism of action, clinical presentation, and treatment

Aims

As an analgesic that acts upon the central nervous system (CNS), tramadol has gained popularity in treating moderate to severe pain. Recently, it has been increasingly reported as a drug of misuse with intentional overdoses or intoxications. This review focuses on tramadol intoxication in humans and its effects on different systems.

Subject and method

This narrative review provides a comprehensive view of the pharmacokinetics, mechanism of action, and incidence of tramadol toxicity with an in-depth look at its side effects. In addition, the main approaches to the management of tramadol poisoning are described.

Results

Tramadol poisoning can affect multiple organ systems: gastrointestinal, central nervous system (seizure, CNS depression, low-grade coma, anxiety, and over time anoxic brain damage), cardiovascular system (palpitation, mild hypertension to life-threatening complications such as cardiopulmonary arrest), respiratory system, renal system (renal failure with higher doses of tramadol intoxication), musculoskeletal system (rhabdomyolysis), endocrine system (hypoglycemia), as well as, cause serotonin syndrome. Seizure, a serious nervous disturbance, is more common in tramadol intoxication than with other opioids. Fatal tramadol intoxications are uncommon, except in ingestion cases concurrent with other medications, particularly CNS depressants, most commonly benzodiazepines, and ethanol.

Conclusion

With the increasing popularity of tramadol, physicians must be aware of its adverse effects, substantial abuse potential, and drug interactions, to weigh its risk–benefit ratio for pain management. Alternative therapies might be considered in patients with a previous overdose history to reduce risks for adverse outcomes.

Team Approach: Complex Regional Pain Syndrome in Children and Adolescents

Children and adolescents with chronic pain are best managed by an interdisciplinary team. In cases of complex regional pain syndrome (CRPS), the interdisciplinary team consists of a pain management specialist, such as an anesthesiologist or physiatrist, a physical therapist, an occupational therapist, a pain psychologist, and an orthopaedist. It may also include other professions, such as a gastroenterologist, psychiatrist, nurse practitioner, nutritionist, endocrinologist, acupuncturist, or social worker. Key factors include rapid recognition of CRPS and the initiation of appropriate treatment, both for the pain syndrome as well as for the orthopaedic injury. Intensive therapies have been shown to be effective in treating CRPS in children. Children often are more responsive to noninvasive treatments than adults.

Perioperative Pain Management and Opioid Stewardship: A Practical Guide

Surgical procedures are key drivers of pain development and opioid utilization globally. Various organizations have generated guidance on postoperative pain management, enhanced recovery strategies, multimodal analgesic and anesthetic techniques, and postoperative opioid prescribing. Still, comprehensive integration of these recommendations into standard practice at the institutional level remains elusive, and persistent postoperative pain and opioid use pose significant societal burdens. The multitude of guidance publications, many different healthcare providers involved in executing them, evolution of surgical technique, and complexities of perioperative care transitions all represent challenges to process improvement. This review seeks to summarize and integrate key recommendations into a "roadmap" for institutional adoption of perioperative analgesic and opioid optimization strategies. We present a brief review of applicable statistics and definitions as impetus for prioritizing both analgesia and opioid exposure in surgical quality improvement. We then review recommended modalities at each phase of perioperative care. We showcase the value of interprofessional collaboration in implementing and sustaining perioperative performance measures related to pain management and analgesic exposure, including those from the patient perspective. Surgery centers across the globe should adopt an integrated, collaborative approach to the twin goals of optimal pain management and opioid stewardship across the care continuum.

Rapid Fire: Polypharmacy in the Geriatric Patient

Increasing prescription drug use trends in the United States affects patients across all ages, but especially the geriatric patient. As patients age, they are at increased risk for adverse events owing to natural changes in body composition and organ function, increased sensitivity to medications, and a higher chance of adverse events from drug-drug interactions and polypharmacy. Falls are common and can increase morbidity and mortality. To mitigate falls, it is imperative to have a comprehensive approach to screening home medication lists, be aware of and avoid high-risk medications, and deprescribe agents that are potentially inappropriate for this patient population.

Dynamic Distribution and Postmortem Redistribution of Tramadol in Poisoned Rats

In the past dozen years, the cases of tramadol intoxication have become frequent in many countries. Most previous studies focused on tramadol's pharmacology, such as pharmacokinetics, pharmacodynamics and pharmacogenetics. However, the dynamic distribution and postmortem redistribution (PMR) of tramadol remain unclear. Our study aimed to investigate these two issues systematically in various specimens of 216 poisoned male rats. A validated gas chromatography-mass spectrometry method was used in this study to measure the concentrations of tramadol. In the first part, 66 tramadol poisoned rats were sacrificed at 11 different time points and their organs were collected separately for the study of tramadol's dynamic distribution, which made it feasible to investigate its PMR later on. The results of this part showed that tramadol's concentrations varied according to the organ and time, and peaked 2 h after intragastric administration in the specimens of liver, kidney, spleen, lung, brain and heart-blood (except stomach and heart). Based on the results of the first part, the concentration of tramadol peaked 2 h in most tissues. Therefore, this time point was used for the study of tramadol's PMR. In the second part, the remaining 150 rats were sacrificed 2 h after intragastric administration of tramadol, and the carcasses were stored under three different conditions (-20, 4 and 20°C). The autopsy was carried out at eight different time points and their organs were collected separately. The results of this part showed that under storage temperatures of -20 and 4°C, the concentrations of tramadol in individual organs showed no significant changes at different time points whereas under a storage temperature of 20°C, the concentrations in certain organs (liver, kidney, spleen, lung, brain and heart-blood) increased significantly at the last few time points. PMR of tramadol was therefore confirmed. The process of PMR of tramadol could be slowed or stopped at lower storage temperatures (-20 or 4°C), which is significant in cases of suspected tramadol poisoning.

Tapentadol, Buprenorphine, and Levorphanol for the Treatment of Neuropathic Pain: a Systematic Review

PURPOSE OF REVIEW

The objective of this systematic review is to present the available evidence for the utilization of the atypical opioids tapentadol, buprenorphine, and levorphanol for the treatment of neuropathic pain.

RECENT FINDINGS

In total, 1619 articles were retrieved of which 10 studies were included. Of 5 included studies pertaining to tapentadol, 4 studies show tapentadol monotherapy to be effective for the treatment of diabetic peripheral neuropathy or chronic, radiating low back pain. Of the 3 studies included for buprenorphine, only one was a randomized controlled trial found not to have a statistically significant reduction in pain with TD buprenorphine likely due to very high withdrawal rates during the trial. Only 2 case reports were included from the available literature for levorphanol providing low-quality anecdotal evidence. The role of tapentadol, buprenorphine, and levorphanol for neuropathic pain conditions requires robust research including randomized controlled trials to evaluate their efficacy and safety.

Characterizing tramadol users with potentially inappropriate co-medications: A latent class analysis among older adults

Background

Although tramadol is an effective weak opioid analgesic, careful monitoring of potential central nervous system adverse reactions in older adults is needed, especially when used with concomitant medications which may trigger the adverse effects. We aimed to characterize tramadol users with potentially inappropriate co-medications in older adults using a latent class analysis (LCA).

Method

Patients aged 65 years or older using tramadol and receiving potentially inappropriate co-medications were included from a nationwide healthcare claims database. We defined antidepressants, first-generation antihistamines, and anxiolytics as potentially inappropriate co-medications. We applied an LCA for grouping tramadol users based on the common characteristics of medication use and healthcare utilization, and each patient was probabilistically assigned to a class. Patients’ characteristics in different latent classes were compared. Potential adverse drug reactions (ADRs) was defined as the any visits for emergency department after the occurrence of potentially inappropriate co-medications. Logistic regression analysis was used to examine the association between latent classes and potential ADRs.

Results

We identified four distinct latent classes of tramadol users representing different patterns of co-medications: multiple potential drug-drug interaction (pDDI) combination users, antihistamines-tramadol users, antidepressants-tramadol users, and anxiolytics-tramadol users. Multiple pDDI combination users showed high proportion of regular tramadol use, tended to visit more medical institutions, and had a high Charlson comorbidity score. The duration of use of potentially inappropriate co-medications with tramadol was the longest in multiple pDDI combination users and the shortest in antihistamines-tramadol users.

When compared with antihistamines-tramadol users, increased potential ADR risk was observed in multiple pDDI combination users (adjusted odds ratio (OR), 1.81; 95% confidence interval (CI), 1.75–1.88), antidepressants-tramadol users (1.24; 1.19–1.29), and anxiolytics-tramadol users (1.04; 1.00–1.08).

Conclusions

Four distinct classes were identified among older adults using tramadol and potentially inappropriate co-medications. Differences in potential ADR risk were observed between these classes. These findings may help to identify patients at a high risk for ADRs owing to potentially inappropriate co-medications with tramadol.

Machine learning algorithms to predict seizure due to acute tramadol poisoning

INTRODUCTION

This study was designed to develop and evaluate machine learning algorithms for predicting seizure due to acute tramadol poisoning, identifying high-risk patients and facilitating appropriate clinical decision-making.

METHODS

Several characteristics of acute tramadol poisoning cases were collected in the Emergency Department (ED) (2013-2019). After selecting important variables in random forest method, prediction models were developed using the Support Vector Machine (SVM), Naïve Bayes (NB), Artificial Neural Network (ANN) and K-Nearest Neighbor (K-NN) algorithms. Area Under the Curve (AUC) and other diagnostic criteria were used to assess performance of models.

RESULTS

In 909 patients, 544 (59.8%) experienced seizures. The important predictors of seizure were sex, pulse rate, arterial blood oxygen pressure, blood bicarbonate level and pH. SVM (AUC = 0.68), NB (AUC = 0.71) and ANN (AUC = 0.70) models outperformed k-NN model (AUC = 0.58). NB model had a higher sensitivity and negative predictive value and k-NN model had higher specificity and positive predictive values than other models.

CONCLUSION

A perfect prediction model may help improve clinicians' decision-making and clinical care at EDs in hospitals and medical settings. SVM, ANN and NB models had no significant differences in the performance and accuracy; however, validated logistic regression (LR) was the superior model for predicting seizure due to acute tramadol poisoning.

Physiologically based pharmacokinetic modeling of tramadol to inform dose adjustment and drug-drug interactions according to CYP2D6 phenotypes

OBJECTIVES

The objective of this study was to establish physiologically based pharmacokinetic (PBPK) models of tramadol and its active metabolite O-desmethyltramadol (M1) and to explore the influence of CYP2D6 gene polymorphism on the pharmacokinetics of tramadol and M1. Furthermore, we used PBPK modeling to prospectively predict the extent of drug-drug interactions (DDIs) in the presence of genetic polymorphisms when tramadol was co-administered with the CYP2D6 inhibitors duloxetine and paroxetine.

METHODS

Plasma concentrations of tramadol and M1 were used to adjust the turnover frequency (K_cat ) of CYP2D6 for phenotype populations with different CYP2D6 genotypes. PBPK models were developed to capture the pharmacokinetics between CYP2D6 extensive metabolizers (EMs), intermediate metabolizers (IMs), poor metabolizers (PMs), and ultra-rapid metabolizers (UMs). The validated models were then used to support dose adjustment in different CYP2D6 phenotypes and to predict the extent of CYP2D6-mediated DDIs when tramadol was co-administered with paroxetine or duloxetine.

RESULTS

The PBPK models we built accurately describe tramadol and M1 exposure in the population with different CYP2D6 phenotypes. In our prediction, the area under the concentration-time curve (AUC_inf-tDlast ) of M1 is 70% lower in PMs than in EMs, 27% lower in IMs, and 15% higher in UMs. Based on the models we built, we suggest that the oral dose of tramadol should be 50% higher for IMs and 25% lower for UMs to achieve an approximately equivalent plasma exposure of M1 as in EMs. When tramadol was co-administered with paroxetine or duloxetine, the magnitude of the inhibitor-substrate interaction was lowest in EMs (0.45), secondary in IMs (0.39), and highest in PMs (0.18) in terms of M1.

CONCLUSION

The current example uses the PBPK model to guide dose adjustment of tramadol and to predict the effect of CYP2D6 genetic polymorphisms on DDIs for rational clinical use of tramadol in the future.

Novel evidence on the effect of tramadol on self-paced high-intensity cycling

The use of tramadol is a controversial topic in cycling. In order to provide novel evidence on this issue, we tested 29 participants in a pre-loaded cycling time trial (TT; a 20-min TT preceded by 40-min of constant work-rate at 60% of the VO_2max) after ingesting 100 mg of tramadol (vs placebo and paracetamol (1.5 g)). Participants performed the Psychomotor Vigilance Task (PVT) at rest and a Sustained Attention to Response Task (SART) during the 60 min of exercise. Oscillatory electroencephalography (EEG) activity was measured throughout the exercise. The results showed higher mean power output during the 20-min TT in the tramadol vs. paracetamol condition, but no reliable difference was reported between tramadol and placebo (nor paracetamol vs. placebo). Tramadol resulted in faster responses in the PVT and higher heart rate during exercise. The main effect of substance was reliable in the SART during the 40-min constant workload (no during the 20-min TT), with slower reaction time, but better accuracy for tramadol and paracetamol than for placebo. This study supports the increased behavioural and neural efficiency at rest for tramadol but not the proposed ergogenic or cognitive (harmful) effect of tramadol (vs. placebo) during self-paced high-intensity cycling.

Refined Prediction of Pharmacokinetic Kratom-Drug Interactions: Time-Dependent Inhibition Considerations

Preparations from the leaves of the kratom plant (Mitragyna speciosa) are consumed for their opioid-like effects. Several deaths have been associated with kratom used concomitantly with some drugs. Pharmacokinetic interactions are potential underlying mechanisms of these fatalities. Accumulating in vitro evidence has demonstrated select kratom alkaloids, including the abundant indole alkaloid mitragynine, as reversible inhibitors of several cytochromes P450 (CYPs). The objective of this work was to refine the mechanistic understanding of potential kratom-drug interactions by considering both reversible and time-dependent inhibition (TDI) of CYPs in the liver and intestine. Mitragynine was tested against CYP2C9 (diclofenac 4'-hydroxylation), CYP2D6 (dextromethorphan O-demethylation), and CYP3A (midazolam 1'-hydroxylation) activities in human liver microsomes (HLMs) and CYP3A activity in human intestinal microsomes (HIMs). Comparing the absence to presence of NADPH during preincubation of mitragynine with HLMs or HIMs, an ∼7-fold leftward shift in IC50 (∼20 to 3 μM) toward CYP3A resulted, prompting determination of TDI parameters (HLMs: K I , 4.1 ± 0.9 μM; k inact , 0.068 ± 0.01 min-1; HIMs: K I , 4.2 ± 2.5 μM; k inact , 0.079 ± 0.02 min-1). Mitragynine caused no leftward shift in IC50 toward CYP2C9 (∼40 μM) and CYP2D6 (∼1 μM) but was a strong competitive inhibitor of CYP2D6 (K i , 1.17 ± 0.07 μM). Using a recommended mechanistic static model, mitragynine (2-g kratom dose) was predicted to increase dextromethorphan and midazolam area under the plasma concentration-time curve by 1.06- and 5.69-fold, respectively. The predicted midazolam area under the plasma concentration-time curve ratio exceeded the recommended cutoff (1.25), which would have been missed if TDI was not considered. SIGNIFICANCE STATEMENT: Kratom, a botanical natural product increasingly consumed for its opioid-like effects, may precipitate potentially serious pharmacokinetic interactions with drugs. The abundant kratom indole alkaloid mitragynine was shown to be a time-dependent inhibitor of hepatic and intestinal cytochrome P450 3A activity. A mechanistic static model predicted mitragynine to increase systemic exposure to the probe drug substrate midazolam by 5.7-fold, necessitating further evaluation via dynamic models and clinical assessment to advance the understanding of consumer safety associated with kratom use.

Preoperative Analgesia, Complications, and Resource Utilization After Total Hip Arthroplasty: Tramadol Is Associated With Less Risk Than Other Preoperative Opioid Medications

BACKGROUND

Preoperative opioid use is known to be detrimental to outcomes after total hip arthroplasty (THA). This is concerning as multiple societies recommend tramadol for the management of arthritis. The purpose of this study was to determine if tramadol is associated with postoperative complications, increased resource utilization, and revision when compared with patients receiving nontramadol opioids (NTOs) and those who are opioid naive (ON).

METHODS

This is a retrospective cohort study using the Truven MarketScan databases (Truven Health, Ann Arbor, MI). Adult patients undergoing primary THA were identified and divided into 4 cohorts based on preoperative opioid medications (ie, ON, tramadol-only [TO], or NTOs; ±tramadol). Demographics, comorbidities, and 90-day complications were collected and compared between cohorts. Revision rates were compared at 3 years. Univariate and multivariate analyses were performed. Finally, preoperative prescription patterns were trended during the study period.

RESULTS

About 198,357 patients, including 18,694 TO and 106,768 ON, were identified. Compared with ON, TO patients had similar rates of complications and revision surgery (P > .05) but had slightly higher emergency department visits (odds ratio [OR], 1.06; 95% confidence interval [95% CI], 1.01-1.12; P = .027), readmissions (OR, 1.16; 95% CI, 1.09-1.22; P < .001), and nonhome discharges (OR, 1.07; 95% CI, 1.02-1.12; P = .010). TO patients had significantly lower odds of incurring most examined complications, including revision surgery, when compared with NTO (P < .05). From 2009 to 2018, the proportion of patients prescribed preoperative opioids decreased.

CONCLUSION

Preoperative TO is associated with less postoperative risk than NTO use and is similar to opioid naivety. Fortunately, the number of patients receiving preoperative NTOs appears to be decreasing. Our results support tramadol as an appropriate pre-THA analgesic.

Considerations When Applying Pharmacogenomics to Your Practice

Many practitioners who have not had pharmacogenomic education are required to apply pharmacogenomics to their practices. Although many aspects of pharmacogenomics are similar to traditional concepts of drug-drug interactions, there are some differences. We searched PubMed with the search terms pharmacogenomics and pharmacogenetics (January 1, 2005, through December 31, 2019) and selected articles that supported the application of pharmacogenomics to practice. For inclusion, we gave preference to national and international consortium guidelines for implementation of pharmacogenomics. We discuss special considerations important in the application of pharmacogenomics to assist clinicians with ordering, interpreting, and applying pharmacogenomics in their practices.

The impact of preoperative tramadol-only use on outcomes following total knee arthroplasty - Is tramadol different than traditional opioids?

BACKGROUND

Opioid use prior to total knee arthroplasty (TKA) is known to have detrimental influence on postoperative outcomes. Whether or not the same is true for tramadol is currently unclear. The aim of this study was to clarify the relationship between preoperative tramadol and postoperative complications.

METHODS

The Truven Marketscan® Databases were used to conduct this retrospective cohort study. Patients undergoing primary TKA were identified and divided into cohorts based on preoperative medication status (i.e. opioid naïve, tramadol-only, or non-tramadol opioids). Patient demographics, comorbidities, and 90-day outcomes were collected and compared between cohorts. Revision rates were analyzed at 1- and 3-years postoperatively. Univariate and multivariate analysis was performed.

RESULTS

336,316 patients were included and 23,097 (6.9%) were preoperative tramadol-only users. Tramadol-only patients (v. opioid naïve) had increased odds of 90-day readmission (OR-1.07, 95%CI 1.02-1.12, p = 0.004), wound complication (OR-1.13, 95%CI 1.01-1.27, p = 0.34), and 3-year revision rates (OR-1.35, 95%CI 1.19-1.53, p < 0.001). However, when compared to the preoperative opioid cohorts, tramadol-only patients had decreased odds of nearly all outcomes. Over the study period, the number of patients receiving preoperative opioids decreased while the proportion of patients prescribed tramadol-only increased.

CONCLUSIONS

While tramadol-only use has lower risk than traditional opioids, tramadol-only use preceding TKA is associated with increased rates of readmission, wound complication and revision surgery. This is important information for prescribers who may be using tramadol to treat symptomatic knee arthrosis prior to arthroplasty referral and for thought leaders producing clinical practice guidelines.

LEVEL OF EVIDENCE

Level III, Prognostic.

Relative addictive potential of opioid analgesic agents

Opioid overdoses and deaths continue to be a problem in the USA with a significant portion related to prescribed opioid analgesic agents. The role of pharmacogentic factors in opioid addiction is an active area of research. While all opioid analgesic agents have some addictive potential, it is clear that there are some with greater addictive potential. Oxycodone is the most widely abused opioid analgesic and it appears to predispose to chronic use with high likability by users. Fentanyl and hydromorphone are both very lipophilic allowing rapid penetration into the CNS, but are not rated as highly as other agents. Providers should consider the risk of addiction with the opioids they prescribe and give those with a lower addictive potential.

Management of postsurgical pain in the community

Following surgery there is often a need for ongoing pain management after the patient is discharged from hospital. This can be made easier if the patient has an appropriate discussion before leaving hospital about what pain they can expect, and they are given a management plan Paracetamol and non-steroidal anti-inflammatory drugs are suitable for most patients. Drugs with a short half-life, such as ibuprofen, may need to be taken regularly Short-acting opioids can have a short-term role, providing guidelines are followed. There is a predictable period of time after surgery when the benefit of an opioid is expected to be maximised before harmful adverse effects will dominate Gabapentinoids are useful for neuropathic pain, but have a limited role in nociceptive pain. Like opioids, they have a risk of misuse The surgeon should be consulted if the patient develops new pain or the postoperative pain becomes more severe Most postsurgical pain will resolve within three months. If not, it is deemed persistent pain that may warrant specialist assessment

Neurotoxic, Hepatotoxic and Nephrotoxic Effects of Tramadol Administration in Rats

The current study was performed to study the tramadol HCL toxic effects on the brain, liver, and kidney of adult male rats. Forty male adult albino rats were divided into 4 groups; the first one was considered as a control group, the others were orally administrated with 25, 50, and 100 b.wt. representing therapeutic, double therapeutic, and 4 times therapeutic doses, respectively, of tramadol HCL daily for 1 month. Serum and brain, hepatic, and renal tissues were collected for biochemical and molecular investigations. Tramadol HCL resulted in a significant increase in the brain serotonin, 8-hydroxy-2'-deoxyguanosine (8-OHdG), and malonyldialdehyde (MDA) levels with a significant decrease in the reduced glutathione (GSH), catalase (CAT), and superoxide dismutase (SOD) activities. At the same line, hepatic and renal 8-OHdG and MDA levels showed a significant increase with a significant decrease in reduced glutathione (GSH), CAT, and SOD activities. In addition, hepatic and renal function parameters including serum alanine amino transferase (ALT), aspartate amino transferase (AST), urea, and creatinine were increased in a dose-dependent manner. At the molecular levels, hepatic cytochrome P5402E1 (CYP2E1), renal Kidney Injury Molecule-1 (KIM-1), and tissue inhibitor of metalloproteinase-1 (TIMP-1) showed also a significant increase in the expression levels. Histopathological evaluation of the brain confirmed the above biochemical results. In conclusion, tramadol HCL induced neurotoxic, hepatotoxic, and nephrotoxic effects in a manner relative to its concentration by affecting brain serotonin levels and hepatic and renal function, with the production of DNA damage and oxidative stress.

Use of Tramadol or Other Analgesics in Patients Treated in the Emergency Department as a Risk Factor for Opioid Use

The objective of this cohort study was to determine the association between the use of tramadol in emergency departments and the later consumption of opioids at the outpatient level in a group of patients from Colombia. Based on a medication dispensation database, patients over 18 years of age treated in different clinics in Colombia who for the first time received tramadol, dipyrone, or a nonsteroidal anti-inflammatory drug (NSAID) in the emergency room between January and December 2018 were identified. Three mutually exclusive cohorts were created, and each patient was followed up for 12 months after the administration of the analgesic to identify new formulations of any opioid. A Cox proportional-hazards regression model was constructed to identify variables associated with receiving a new opioid. A total of 12,783 patients were identified: 6020 treated with dipyrone, 5309 treated with NSAIDs, and 1454 treated with tramadol. The mean age was 47.1 ± 20.4 years, and 61.6% were women. A total of 17.3% (n = 2207) of all patients received an opioid during follow-up. Those treated with tramadol received a new opioid with a higher frequency (n = 346, 23.8%) than the other cohorts (14.7% NSAIDs and 17.9% dipyrone, both p < 0.001). In the tramadol group, using more than 10 mg of morphine equivalents was associated with a greater use of new opioids (HR:1.47, 95%CI:1.12-1.93). Patients treated with tramadol in emergency departments have a higher risk of opioid use at the one-year follow-up than those treated with NSAIDs or dipyrone.

Pain management in patients with chronic kidney disease and end-stage kidney disease

PURPOSE OF REVIEW

This review evaluates current recommendations for pain management in chronic kidney disease (CKD) and end-stage kidney disease (ESKD) with a specific focus on evidence for opioid analgesia, including the partial agonist, buprenorphine.

RECENT FINDINGS

Recent evidence supports the use of physical activity and other nonpharmacologic therapies, either alone or with pharmacological therapies, for pain management. Nonopioid analgesics, including acetaminophen, topical analgesics, gabapentinoids, serotonin-norepinephrine reuptake inhibitors, and TCA may be considered based on pain cause and type, with careful dose considerations in kidney disease. NSAIDs may be used in CKD and ESKD for short durations with careful monitoring. Opioid use should be minimized and reserved for patients who have failed other therapies. Opioids have been associated with increased adverse events in this population, and thus should be used cautiously after risk/benefit discussion with the patient. Opioids that are safer to use in kidney disease include oxycodone, hydromorphone, fentanyl, methadone, and buprenorphine. Buprenorphine appears to be a promising and safer option due to its partial agonism at the mu opioid receptor.

SUMMARY

Pain is poorly managed in patients with kidney disease. Nonpharmacological and nonopioid analgesics should be first-line approaches for pain management. Opioid use should be minimized with careful monitoring and dose adjustment.

The role of cannabinoid 1 receptor in the nucleus accumbens on tramadol induced conditioning and reinstatement

AIMS

Previous investigations demonstrated that tramadol, as a painkiller, similar to morphine induces tolerance and dependence. Furthermore, the cannabinoid receptor 1 (CB1R) located in the nucleus accumbens (NAc) plays a critical role in morphine-induced conditioning. Therefore, the main objective of this study was to evaluate the role of NAc CB1R in tramadol induced conditioning and reinstatement.

MAIN METHODS

In the present experiment, the effect of NAc CB1 receptors on tramadol induced conditioning was tested by microinjecting of arachidonylcyclopropylamide (ACPA, CB1R agonist) and AM 251 (CB1R inverse agonist) in the NAc during tramadol-induced conditioning in the adult male Wistar rats. In addition, the role of NAc CB1R in the reinstatement was also evaluated by injecting ACPA and AM 251 after a 10-days extinction period.

KEY FINDINGS

The obtained data revealed that the administration of tramadol (1,2, and 4 mg/kg, ip) dose-dependently produced conditioned place preference (CPP). Moreover, intra-NAc administration of ACPA (0.25, 0.5, and 1 μg/rat) dose-dependently induced conditioning, while the administration of AM-251 (30, 60, and 120 ng/rat) induced a significant aversion. In addition, the administration of a non-effective dose of AM251 during tramadol conditioning inhibited conditioning induced by tramadol. On the other hand, the administration of ACPA after extinction induced a significant reinstatement. Notably, the locomotor activity did not change among groups.

SIGNIFICANCE

Previous studies have shown that tramadol-induced CPP occurs through μ-opioid receptors. The data obtained in the current study indicated that CB1R located in the NAc is involved in mediating conditioning induced by tramadol. Besides, CB1R also plays a vital role in the reinstatement of tramadol-conditioned animals. It might be due to the effect of opioids on enhancing the level of CB1R.

Use of tramadol and other analgesics following media attention and risk minimization actions from regulators: a Danish nationwide drug utilization study

Purpose

To describe the use of tramadol and other analgesics in Denmark focusing on the impact of media attention (June and December 2017) and regulatory actions (September 2017 and January 2018) on the use of tramadol.

Methods

Using nationwide registries, we identified all adults who filled a prescription for tramadol and other analgesics from 2014 to 2019. We described incidence rates, prevalence proportions, and total use of tramadol and other analgesics over time. We also described switching between analgesics, treatment duration, skewness in drug use, and doctor-shopping.

Results

From early 2017 until the end of 2019, total tramadol use decreased markedly while the use of morphine and oxycodone decreased slightly. The quarterly prevalence of tramadol use decreased from 32/1000 individuals in 2014 to 18/1000 at the end of 2019, dropping mainly at the time of media attention. Concomitantly, the quarterly prevalence increased for oxycodone (from 5.1 to 8.2) and morphine (from 8.5 to 9.8), mainly due to more short-term and sporadic users, and decreased for codeine (14 to 9.6). From 2014 to mid-2017, the incidence of tramadol use was stable (around 2.2/1000 person-months) but dropped in June 2017 to 1.7/1000, coinciding with the media attention. The incidence of tramadol use continued to decrease (to 1.1/1000 at the end of 2019).

Conclusion

We identified a decline in tramadol use coinciding with the media attention in 2017 and continuing during regulatory actions. There was generally no evidence of unintended effects on the utilization of opioids related to the media attention and regulatory actions.

Electronic supplementary material

The online version of this article (10.1007/s00228-020-03016-6) contains supplementary material, which is available to authorized users.

Analgesic and Antiallodynic Effects of 4-Fluoro-N-(4-Sulfamoylbenzyl) Benzene Sulfonamide in a Murine Model of Pain

INTRODUCTION

Physical, chemical, thermal injuries along with infectious diseases lead to acute pain with associated inflammation, being the primary cause of hospital visits. Moreover, neuropathic pain associated with diabetes is a serious chronic disease leading to high morbidity and poor quality of life.

OBJECTIVE

Earlier multiple sulphonamides have been reported to have an antinociceptive and antiallodynic profile. 4-Fluoro-N-(4-sulfamoylbenzyl) Benzene Sulfonamide (4-FBS), a synthetic sulfonamide with reported carbonic anhydrase inhibitory activity, was investigated for its potential effects in mice model of acute and diabetic neuropathic pain.

METHODS AND RESULTS

4-FBS was given orally (p.o.) one hour before the test and then mice were screened for antinociceptive activity by using the tail immersion test, which showed significant antinociceptive effect at both 20 and 40 mg/kg doses. To explore the possible mechanisms, thermal analgesia of 4-FBS was reversed by the 5HT3 antagonist ondansetron 1mg/kg intraperitoneally (i.p.) and by the µ receptor antagonist naloxone (1 mg/kg i.p.), implying possible involvement of serotonergic and opioidergic pathways in the analgesic effect of 4-FBS. Diabetes was induced in mice by a single dose of streptozotocin (STZ) 200 mg/kg i.p. After two weeks, animals first became hyperalgesic and progressively allodynic in the fourth week, which was evaluated through behavioral parameters like thermal and mechanical tests. 4-FBS at 20 and 40 mg/kg p.o. significantly reversed diabetes-induced hyperalgesia and allodynia at 30, 60, 90, and 120 minutes.

CONCLUSION

These findings are significant and promising while further studies are warranted to explore the exact molecular mechanism and the potential of 4-FBS in diabetic neuropathic pain.

Green spectrofluorimetric methods for tramadol assay with ibuprofen or chlorzoxazone: comparison of greenness profiles

At this time, green analytical chemistry is gaining more interest and concern. The present work details three green spectrofluorimetric methods for tramadol (TRM) determination using ibuprofen (IBU) (mixture 1) and chlorzoxazone (CLZ) (mixture 2). In first method, two excitation wavelengths (λ_ex ), 220 and 280 nm, were used to record the emission spectra for IBU and TRM, respectively (mixture 1) followed by a first derivative treatment. For mixture 2, one λ_ex (280 nm) was optimum for both drugs followed by a first derivative technique for TRM and a second derivative for CLZ determinations. The second method measured the first derivative values for synchronous spectra using constant-wavelength mode at 280 nm for TRM and 260 nm for IBU, and at 270 nm for TRM and 292 nm for CLZ. The third method used constant-energy mode to record synchronous spectra. First derivative values were computed at 282 nm for TRM and 260 nm for IBU in mixture 1 and at 272 nm for TRM and 292 nm for CLZ in mixture 2. ICH validation guidelines were assessed in full and assay of the two TRM binary mixtures in their drug products was successful. Green profile evaluation for the developed methods compared with the reported chromatographic methods was performed using the 'analytical eco-scale' and the 'green analytical procedure index'. These two assessment tools corroborated that the proposed methods achieved the most green parameters, therefore recommending their use as a green option for analyzing the studied drugs in bulk and dosage forms for routine quality control.

Clinical Tolerability and Safety of Tramadol in Hospitalized Patients

Tramadol is a schedule IV, monoaminergic and μ-opioid-receptor analgesic with unique pharmacology properties. Though it is well established and widely utilized, there is little guidance on tramadol's place in therapy, including tolerability, safety and monitoring guidelines. Retrospective chart review of 250 patients who received oral tramadol during their hospitalization from January 1, 2018 to December 31, 2018. Of the 250 patients, 10.8% had cancer as their primary diagnosis while 8.8% were admitted for hematologic reasons. 79.1% of patients had acute pain. Palliative care consult or ICU admission resulted in significant discontinuation of tramadol (p < 0.05 odds ratio 6.88, 2.39). There was no significant relationship of hypoglycemia when evaluating days on tramadol, total number of doses on tramadol, and MEDD start and end (p = 0.36, 0.88, 0.15, 0.23 consecutively). The longer that patients were on tramadol and the more doses they received during their inpatient stay, the greater risk of a severe drug-drug interaction (p < 0.05; R 0.29). In hospitalized patients, the risk of major and severe drug-drug interactions with tramadol increased with dose and duration. Hospital medicine, bone marrow transplant, and emergency medicine teams predominantly used tramadol.

Traitements pharmacologiques et non pharmacologiques de la douleur neuropathique : une synthèse des recommandations françaises

Les douleurs neuropathiques (DN) restent très difficiles à soulager. Plusieurs recommandations ont été proposées au cours de ces dernières années, mais aucune n’a pris en compte à ce jour l’ensemble des approches thérapeutiques disponibles. Nous avons réalisé une revue systématique portant sur toutes les études concernant le traitement des DN périphériques et centrales de l’adulte et de l’enfant, publiées jusqu’en janvier 2018 et avons évalué la qualité des études et le niveau de preuve des traitements au moyen du système GRADE. Les principaux critères d’inclusion étaient l’existence d’une DN chronique (≥ 3 mois), une méthodologie contrôlée et randomisée, un suivi supérieur ou égal à trois semaines, un nombre de patients supérieur ou égal à dix par groupe et une évaluation en double insu pour les traitements pharmacologiques. Sur la base du GRADE, nous recommandons en première intention les antidépresseurs inhibiteurs mixtes de recapture des monoamines (duloxétine et venlafaxine), les antidépresseurs tricycliques, la gabapentine pour toute DN, et les emplâtres de lidocaïne 5 % et la stimulation électrique transcutanée pour les DN périphériques localisées. Nous recommandons en deuxième intention la prégabaline, le tramadol (avec les précautions d’emploi afférentes aux opioïdes) et certaines associations pharmacologiques (antidépresseurs et gabapentine ou prégabaline) pour toute DN, et les patchs de haute concentration de capsaïcine (8 %) et la toxine botulique de type A (en milieu spécialisé) pour les DN périphériques localisées. Nous recommandons en troisième intention la stimulation magnétique transcrânienne répétitive à haute fréquence du cortex moteur (en milieu spécialisé) et les opioïdes forts (en l’absence d’alternative et en respectant les précautions d’emploi afférentes aux opioïdes) pour toute douleur neuropathique, et la stimulation médullaire pour les douleurs radiculaires chroniques postchirurgicales et la polyneuropathie diabétique douloureuse. La psychothérapie (thérapie cognitivocomportementale et thérapie de pleine conscience) peut être recommandée en deuxième intention en association avec les traitements précédents.

Initiation of Transdermal Fentanyl Among US Commercially Insured Patients Between 2007 and 2015

INTRODUCTION

This study examined patterns of initial transdermal fentanyl (TDF) claims among US commercially insured patients and explored the risk of 30-day hospitalization among patients with and without prior opioid exposure necessary to produce tolerance.

DESIGN

A retrospective cohort study of initial outpatient TDF prescriptions.

SETTING

A 10% random sample of commercially insured enrollees within the IQVIA Health Plan Claims Database (formerly known as PharMetrics Plus).

SUBJECTS

Individuals with a claim for TDF between 2007 and 2015.

METHODS

The primary exposure was a new transdermal fentanyl claim, and the primary outcome was guideline concordance based on time and dose exposure.

RESULTS

Among the 24,770 patients in the cohort, 4,848 (20%) patients had sufficient time exposure to opioids before TDF. Among those with sufficient time exposure, 3,971 (82%) had adequate opioid exposure based on the US Food and Drug Administration (FDA) package insert dosing guidance. Overall, 3,971 of the 24,770 (16%) patients received guideline-consistent TDF. An exploratory analysis of 30-day hospitalization after a TDF claim did not detect a difference in odds between guideline-consistent or -inconsistent groups when adjusted for variables known to influence the risk of opioid-induced respiratory depression.

CONCLUSIONS

A majority of patients met FDA opioid dose thresholds for TDF but had insufficient time exposure based on package insert recommendations for tolerance. Exploratory analysis did not detect a difference in odds for all-cause hospitalization or respiratory-related 30-day hospitalization between guideline-consistent or -inconsistent TDF claims. Prescribers should continue to adhere to FDA TDF labeling, although certain aspects of the labeling should be reevaluated or clarified.

Evaluation of Drug Abuse in Patients With Lifelong Premature Ejaculation: A Cross-Sectional Study

Introduction

Most studies investigate sexual dysfunction in drug abusers; however, there are no data available about the pattern of drug abuse in patients with lifelong premature ejaculation (PE).

Aim

To assess the pattern of drug abuse in patients with lifelong PE and to evaluate its potential effect on their hormonal profile.

Methods

A cross-sectional study included patients with lifelong PE (n = 76) with no prescribed medications for 1 month and age-matched control without PE (n = 48). Participants were evaluated by history, examination, Arabic index of PE, and hormonal profile. A urine sample was screened by dipstick kits for the following drug abuse tramadol, opiate, tetrahydrocannabinol (cannabis), amphetamine, barbiturate, cocaine, and benzodiazepines. Positive results were confirmed with a immunoassay drug analyzer.

Main outcome measures

The outcomes of this study are positive and negative drug abuse and hormonal profile changes.

Results

Control patients and patients with PE showed median (interquartile range) of age 43 (33–46.8) and 38.5 (31–45) years, respectively. Drug abuse testing results showed significantly high positive drug abuse in patients with PE, 26 of 76 (34.2%), in comparison with control, 9 of 48 (19.1%) (P = .05). The most commonly abused drug was tetrahydrocannabinol in control, 3 of 9 (33.3%), and tramadol, 12 of 26 (46.2%), in patients with PE. Control patients and patients with PE with positive drug abuse had significantly higher smoking percent (P < .0001) and higher positive drug abuse history (P < .0001). However, there was no relationship between drug abuse and PE severity, and there were no significant changes in their hormonal profile.

Conclusions

Drug abuse is high among patients with lifelong PE in Upper Egypt, with tramadol being the comment drug. Drug abuse is common among smokers. However, no hormonal disturbance could be shown in drug abuse patients. Drug abuse might be considered in the evaluation of patients with PE.

Mohammed SA, Abdelhamed A, El Sayed RM. Evaluation of Drug Abuse in Patients With Lifelong Premature Ejaculation: A Cross-Sectional Study. Sex Med 2020;8:608–614.

Pain management in hidradenitis suppurativa and a proposed treatment algorithm

Pain contributes substantially to reduced quality of life in individuals living with hidradenitis suppurativa (HS). Although improved understanding of HS pathogenesis and treatment has resulted in improved evidence-based HS management guidelines, comprehensive pain management guidelines have yet to be developed. Few HS-specific data exist to guide pharmacologic analgesia; however, recognizing HS pain as either acute or chronic and predominantly nociceptive (aching and gnawing pain due to tissue damage) versus neuropathic (burning-type pain due to somatosensory nervous system dysfunction) provides a conceptual framework for applying outside pain management practices to HS management. This article incorporates the best available evidence from the HS and pain literature to propose an HS pain algorithm that integrates psychological, pharmacologic, and complementary and alternative treatment modalities.

Preclinical assessment of tramadol abuse potential: Effects of acute and repeated tramadol on intracranial self-stimulation in rats

BACKGROUND

Tramadol is a widely used analgesic that activates mu-opioid receptors (MOR) and inhibits serotonin and norepinephrine transporters. This mixed pharmacology may limit both its own abuse potential and its modulation of abuse potential of other MOR agonists.

AIMS

This study used an intracranial self-stimulation (ICSS) procedure to compare abuse-related effects produced by acute or repeated treatment with tramadol or morphine in rats. Abuse potential in ICSS procedures is indicated by a drug-induced increase (or 'facilitation') of ICSS responding.

METHODS

Adult male Sprague-Dawley rats were implanted with electrodes targeting the medial forebrain bundle and trained to respond on a lever for pulses of electrical brain stimulation. Tramadol effects were evaluated after acute administration (3.2-32 mg/kg) in the absence or presence of the opioid antagonist naltrexone, the CYP2D6 hepatic-enzyme inhibitor quinine or a combination of both. Additionally, both tramadol and morphine were also tested before and after repeated tramadol (32 mg/kg/day for six days) or repeated morphine (3.2 mg/kg/day for six days).

RESULTS

Acute tramadol produced primarily ICSS rate-decreasing effects that were antagonised by naltrexone but not by quinine or naltrexone + quinine. Tramadol also produced little or no ICSS facilitation after repeated tramadol or repeated morphine, and repeated tramadol did not enhance ICSS facilitation by morphine. By contrast, morphine-induced ICSS facilitation was enhanced by repeated morphine treatment.

CONCLUSIONS

These results suggest that tramadol has lower abuse potential than other abused MOR agonists and that repeated tramadol exposure produces relatively little enhancement of abuse potential of other MOR agonists.

Enhanced Recovery and Surgical Optimization Protocol for Minimally Invasive Gynecologic Surgery: An AAGL White Paper

This is the first Enhanced Recovery After Surgery (ERAS) guideline dedicated to standardizing and optimizing perioperative care for women undergoing minimally invasive gynecologic surgery. The guideline was rigorously formulated by an American Association of Gynecologic Laparoscopists Task Force of US and Canadian gynecologic surgeons with special interest and experience in adapting ERAS practices for patients requiring minimally invasive gynecologic surgery. It builds on the 2016 ERAS Society recommendations for perioperative care in gynecologic/oncologic surgery by serving as a more comprehensive reference for minimally invasive endoscopic and vaginal surgery for both benign and malignant gynecologic conditions. For example, the section on preoperative optimization provides more specific recommendations derived from the ambulatory surgery and anesthesia literature for the management of anemia, hyperglycemia, and obstructive sleep apnea. Recommendations pertaining to multimodal analgesia account for the recent Food and Drug Administration warnings about respiratory depression from gabapentinoids. The guideline focuses on workflows important to high-value care in minimally invasive surgery, such as same-day discharge, and tackles controversial issues in minimally invasive surgery, such as thromboprophylaxis. In these ways, the guideline supports the American Association of Gynecologic Laparoscopists and our collective mission to elevate the quality and safety of healthcare for women through excellence in clinical practice.

Tentative identification of gefitinib metabolites in non-small-cell lung cancer patient plasma using ultra-performance liquid chromatography coupled with triple quadrupole time-of-flight mass spectrometry

Background

Gefitinib is an orally potent and selective ATP-competitive inhibitor of epidermal growth factor receptor (EGFR) tyrosine kinase and is commonly used to treat locally advanced or metastatic non-small-cell lung cancer (NSCLC) with sensitive EGFR mutations. Multiple adverse effects associated with gefitinib, including liver and lung injuries, severe nausea, and diarrhea, have limited its clinical application. Xenobiotic-induced bioactivation is thought to be an important reason for gefitinib toxicity, which encouraged us to clarify the metabolism of gefitinib in NSCLC patients.

Materials and methods

An ultra-performance liquid chromatography coupled with triple quadrupole time-of-flight mass spectrometry (UPLCQ-TOF-MS) method was established to tentatively identify the metabolites of gefitinib in human plasma. The extracted ion chromatogram peak intensity threshold was set at 1500 cps with minimum MS and MS/MS peak intensities of 400 and 100 cps, respectively.

Results

A total of 18 tentative metabolites were identified. Eight novel tentative metabolites with metabolic changes in dechlorination, defluorination, and hydrogenation on the quinazoline skeleton; removal of a partial or complete 3-chloro-4-fluoroaniline-substituted group; and sulfate conjugation and taurine conjugation were newly discovered in human plasma. Based on structural analysis of the tentative metabolites, the metabolic pathways were proposed. In addition, the pathways of dechlorination, defluorination, and hydrogenation on the quinazoline skeleton; removal of partial or complete 3-chloro-4-fluoroaniline-substituted groups; and sulfate conjugation and taurine conjugation in humans in vivo indicate that novel metabolic pathways exist in humans.

Conclusions

In summary, the metabolism of gefitinib in humans in vivo is extensive and complex. Based on in vivo evidence, the propoxy-morpholine ring side chain and O-methyl group are the critical metabolic regions of gefitinib in humans. The novel metabolic pathways differ from those of in vitro studies, suggesting that intestinal floral metabolism might be involved.

Association between opioid use disorder (tramadol) and serum level of interleukin-2

Background

Tramadol hydrochloride is a centrally acting analgesic drug that has turned out to be a drug of growing interest due to its success in the management of pain in humans. By considering the twin mechanism of action of tramadol, as the activation of the opioid and of the monoaminergic systems, the potential immunological effects of this drug should be considered and be evaluated. Studies show that Tramadol induces an improvement of postoperative immune suppression and increases NK cell activity, lymphocyte proliferation, and IL-2 production which may be linked to its addictive potentiality. The present study aims to investigate the possible association between opioid use disorder (tramadol) and the serum level of interleukin-2 (IL-2).

An observational cross sectional study conducted at the Outpatient Clinic and Inpatient Unit of the Addiction Management Unit of the Neurology and Psychiatry Department of Assiut University Hospital. Assessment of serum level of IL-2 for 59 male patients diagnosed with opioid use disorder (tramadol) according to DSM-5 compared to 32 cross-matched male individuals as a control group.

Results

Comparing the serum level of IL-2 in patients with opioid use disorder (tramadol) with that of the controls, it was found that the patients with opioid use disorder (tramadol) have significantly higher serum level of IL-2 (318.69 ± 35.89) than that of controls (260.45 ± 30.08) (P = 0.01). Patients with tramadol urine assay (> 200 ng/ml) have significantly higher serum level of IL-2.

Conclusion

The current study found that patients with opioid use disorder (tramadol) have significantly elevated serum levels of IL-2 than healthy controls. Also, this elevation was dose related.

Tramadol for the Management of Opioid Withdrawal: A Systematic Review of Randomized Clinical Trials

The increase in the prescription of opioid medications has resulted in a wildfire of misuse of opioids, both for medical and non-medical reasons, with over 1.7 million people in the United States (US) suffering from distinct disorders owing to opioid use. While various medications, such as methadone, buprenorphine, and naloxone, among others, have been used in treating opioid withdrawal symptoms, concerns of the potential abuse of these drugs, the cost of procurement, legislations, and prescription policies have risen. In recent times, tramadol has been considered a viable replacement for some of these treatment regimes. Tramadol is a synthetic analgesic that acts centrally, possessing opioid-like effects due to the binding of its metabolite with the mu (µ)-opioid receptor, yet with low potential for abuse. Several clinical studies conducted in the past ten years have identified the effects of tramadol in opioid withdrawal cases. The results showed that it exhibits better efficacy and tolerance with fewer side effects in specific clinical scenarios as compared to existing available detox management. We aim to examine the properties of tramadol in opioid withdrawal through this systematic review of clinical studies on humans.

Toxicology of tramadol following chronic exposure based on metabolomics of the cerebrum in mice

Tramadol is an opioid used as an analgesic for treating moderate or severe pain. The long-term use of tramadol can induce several adverse effects. The toxicological mechanism of tramadol abuse is unclear. Metabolomics is a very useful method for investigating the toxicology of drug abuse. We investigated the impact of chronic tramadol administration on the cerebrum of mice, focusing on the metabolites after tramadol administration. The mice received 20 or 50 mg/kg body weight tramadol dissolved in physiological saline daily for 5 weeks via oral gavage. Compared with the control group, the low dose tramadol group showed seven potential biomarkers, including gamma-hydroxybutyric acid, succinate semialdehyde, and methylmalonic acid, which were either up- or down-regulated. Compared with the control group, the high dose tramadol group showed ten potential biomarkers, including gamma-hydroxybutyric acid, glutamine, and O-phosphorylethanolamine, which were either up- or down-regulated. The up-regulated gamma-hydroxybutyric acid and the down-regulated succinate semialdehyde revealed that the neurotransmitter system was disrupted after tramadol abuse. Compared with the low dose tramadol group, there were twenty-nine potential biomarkers in the high dose tramadol group, mainly related to the pentose phosphate pathway and glycerophospholipid metabolism. In conclusion, metabolomics in the tramadol abuse group demonstrated that long-term tramadol abuse can result in oxidative damage, inflammation, and disruption of the GABA neurotransmitter system, which will help to elucidate the toxicology of tramadol abuse.

Assessment of tramadol pharmacokinetics in correlation with CYP2D6 and clinical symptoms

Objectives Due to lack of adequate data on tramadol kinetic in relevance of CYP2D6 toxicity, this study was designed to investigate the effect of CYP2D6 phenotype in tramadol poisoning. The saliva, urine and blood samples were taken at the admission time. Consequently, concentration of tramadol and its major metabolites were measured. Methods A pharmacokinetic and metabolic study was developed in cases of tramadol poisoned (n=96). Cases of tramadol poisoned evidenced seizure, hypertension, dizziness, nausea and vomiting symptoms participated. Results Female cases showed higher N-desmethyltramadol (M2) tramadol concentrations than male cases: in urine (40.12 ± 124.53 vs. 7.3 ± 7.13), saliva (16.91 ± 26.03 vs. 5.89 ± 7.02), and blood (1.11 ± 1.56 vs. 0.3 ± 0.38) samples. Significant correlation between blood, saliva, and urine concentrations were found (r = 0.5). Based on the metabolic ratio of O-desmethyltramadol (M1) of male (0.53 ± 0.22) and female (0.43 ± 0.26), poisoning and severe symptoms like seizure in female occurs statistically fewer (13.04%) than in male (50.6%). Assessment of CYP2D6 phenotype showed all of the participants were extensive metabolizers (EM) and their phenotype was associated with clinical symptoms. Conclusions According to our results, M1 as a high potent metabolite has an important role in toxicity and the likelihood of poisoning in people with EM phenotype. Finally, tramadol metabolic ratio may justify the cause of various symptoms in human tramadol poisoning.

Assessment of tramadol pharmacokinetics in correlation with CYP2D6 and clinical symptoms

Objectives Due to lack of adequate data on tramadol kinetic in relevance of CYP2D6 toxicity, this study was designed to investigate the effect of CYP2D6 phenotype in tramadol poisoning. The saliva, urine and blood samples were taken at the admission time. Consequently, concentration of tramadol and its major metabolites were measured. Methods A pharmacokinetic and metabolic study was developed in cases of tramadol poisoned (n=96). Cases of tramadol poisoned evidenced seizure, hypertension, dizziness, nausea and vomiting symptoms participated. Results Female cases showed higher N-desmethyltramadol (M2) tramadol concentrations than male cases: in urine (40.12 ± 124.53 vs. 7.3 ± 7.13), saliva (16.91 ± 26.03 vs. 5.89 ± 7.02), and blood (1.11 ± 1.56 vs. 0.3 ± 0.38) samples. Significant correlation between blood, saliva, and urine concentrations were found (r = 0.5). Based on the metabolic ratio of O-desmethyltramadol (M1) of male (0.53 ± 0.22) and female (0.43 ± 0.26), poisoning and severe symptoms like seizure in female occurs statistically fewer (13.04%) than in male (50.6%). Assessment of CYP2D6 phenotype showed all of the participants were extensive metabolizers (EM) and their phenotype was associated with clinical symptoms. Conclusions According to our results, M1 as a high potent metabolite has an important role in toxicity and the likelihood of poisoning in people with EM phenotype. Finally, tramadol metabolic ratio may justify the cause of various symptoms in human tramadol poisoning.

ADME and toxicity considerations for tramadol: from basic research to clinical implications

INTRODUCTION

Tramadol is widely being used in chronic pain management for improving patients' life quality and reducing trauma. Although it is listed in several medicinal guidelines, its use is controversial because of the conflicting results obtained in pharmacokinetic/pharmacodynamic studies. This multi-receptor drug acts as µ₁ opioid receptor agonist, monoamine reuptake inhibitor, and inhibitor of ligand-gated ion channels and some special protein-coupled receptors.

AREAS COVERED

This review provides a comprehensive view on the pharmacokinetic, pharmacodynamic, and toxicity of tramadol with a deep look on its side effects, biochemical and pathological changes, and possible drug interactions. In addition, the main ways of tramadol poisoning management describe according to in vivo and clinical trial studies.

EXPERT OPINION

Given the broad spectrum of targets, increasing the cases of overdoses and toxicity, and probable drugs interaction, it is necessary to take another look at the pharmacology of tramadol. Regarding the adverse effects of tramadol on different tissues, especially the nervous system and liver tissue, more attentions to tramadol metabolites, their interaction with other drugs, and active agents seem critical. Seizure as the most cited effect of tramadol and its destructive effects on tissues would alleviate by co-administration with drugs with antioxidant properties.

Evaluation of the effects of a drug with fiscalized substance dispensation, health education, and pharmacovigilance continuing education program in Colombia drugstores and drugstores/pharmacies: study protocol of a multicenter, cluster-randomized controlled trial

Background

Health disorders, due to the use of drugs with fiscalized substances, including controlled substances, have become a common problem in Colombia. Multiple reasons can help explain this problem, including self-medication, since access to these drugs may be easier. Also, there is a lack of knowledge that these drugs are safer than illicit drugs. The use of these drugs without a valid medical prescription and follow-up can have negative consequences such as drug abuse, addiction, and overdose, and eventually, have negative health consequences. Pharmacy staff is essential to both assure the correct drug use and minimize prescription errors to help outpatients have better management of their pharmacotherapy. For this reason, it is necessary to increase key competencies like knowledge, skills, and attitudes in the pharmacy staff of ambulatory (outpatients) pharmacies.

Methods

This study is a prospective, cluster-randomized, parallel-group, multicenter trial of drugstores and drugstores/pharmacies (ambulatory pharmacies). The study is designed to determine the effectiveness of a drug with fiscalized substance dispensation, health education, and pharmacovigilance continuing education program in drugstores and drugstores/pharmacies. Pharmacy staff will be randomly selected and assigned to one of the study groups (intervention or control). The intervention group will receive a continuing education program for over 12 months. The control group will receive only general information about the correct use of complex dosage forms. The primary objective is to evaluate the effectiveness of a continuing education program to improve pharmacy staff competencies (knowledge, skills, and attitudes) to improve the ambulatory (outpatient) pharmacy services: dispensation, health education, and pharmacovigilance of drugs with fiscalized substances. The secondary outcomes include (a) processes associated with the management of drugs with fiscalized substances in drugstores and drugstores/pharmacies, including regulation compliance; (b) degree of implementation of ambulatory (outpatient) pharmacy services targeting these drugs in drugstores and drugstores/pharmacies; (c) patient satisfaction with such services; and (d) pharmacy staff satisfaction with the continuing education program.

Discussion

This clinical trial will establish whether providing a continuing education program for the adequate utilization of drugs with fiscalized substances improves pharmacy staff competencies regarding these drugs.

Trial registration

ClinicalTrials.gov NCT03388567. Registered on 28 November 2017. First drugstore or drugstore/pharmacy randomized on December 1, 2018.

Protocol version

0017102017MC

Genetics and Gender in Acute Pain and Perioperative Opioid Analgesia

Experimental and clinical acute pain research in relation to biological sex and genetics started in the 1980s. Research methods became more powerful and sensitive with the advancement in affordable gene sequencing methods and high-throughput genetic assays. Decades of research has identified several potential pharmaceutical targets, providing insights into future research direction, and understanding of acute pain and opioid analgesic effects in the clinical setting. However, there is insufficient evidence to make generalized recommendations for using genetic tests for clinical practice of acute pain management.

Tramadol/Diclofenac Fixed-Dose Combination: A Review of Its Use in Severe Acute Pain

Pain is a health issue affecting all populations, regardless of age, gender, economic status, race, or geography. Acute pain is the most common type of pain, with a complex aetiology. Inadequately managed acute pain adversely affects quality of life and imposes significant economic burden. The majority of the available pain-relieving drugs have monomodal mechanisms of analgesia, which necessitates combining drugs with non-redundant mechanisms of action in order to provide adequate pain relief and reduce the side effects from higher doses of individual drugs. In this regard, combining an oral opioid (such as codeine or tramadol) and a non-opioid (such as paracetamol or non-steroidal anti-inflammatory drug) offers a plausible option. Tramadol/diclofenac fixed-dose combination (FDC) is one such analgesic combination which has demonstrated promising clinical activity via its multimodal mechanisms of action. This review seeks to provide an up-to-date narrative on the current scientific literature regarding the pharmacological properties, clinical efficacy, and tolerability of tramadol/diclofenac FDC in the treatment of acute severe pain. A comprehensive, qualitative review of the literature was conducted using a structured search strategy in Medline/PubMed and additional Internet-based sources to identify relevant studies. Based on the available scientific literature, evidence of the efficacy and safety of tramadol/diclofenac FDC for treatment of patients with acute severe pain, including musculoskeletal pain, postoperative pain, and acute flare-up of osteoarthritis or rheumatoid arthritis, appears to be substantial. Although additional comparative studies would be required to definitively position tramadol/diclofenac FDC with respect to other analgesic combinations, the available data suggest that tramadol/diclofenac FDC is a valuable treatment option for patients with acute severe pain.