Pregabalin-induced first degree atrioventricular block in a young patient treated for pain from extrapulmonary tuberculosis

Drug clustering to anticipate new aspects of drug safety profile: Application to gabapentinoids and other voltage-gated calcium channel ligand drugs

AIMS

Gabapentin and pregabalin bind to α2-δ subunit of voltage-gated calcium channels (Cav ). Other drugs targeting Cav include cardiovascular calcium channel blockers (CCBs) and anticonvulsants (levetiracetam, ethosuximide and zonisamide). In addition to pharmacodynamics, the safety profile of gabapentinoids seems to overlap with the one of cardiovascular CCBs (oedema) and Cav -blocking anticonvulsants (suicide and ataxia). The objective of this study was to cluster the safety profile of different Cav -ligand drugs by focusing on whether gabapentinoids present a distinct adverse drug reaction (ADR) signature from cardiovascular CCBs and anticonvulsants.

METHODS

We extracted all ADRs with at least one significant disproportionate reporting (reporting odds ratio) related to gabapentinoids, CCBs or anticonvulsants in VigiBase. After principal component analysis preprocessing, a hierarchical ascendent classification was performed to cluster gabapentinoids and other Cav -ligand drugs that share a similar ADR signature. The robustness of the results was determined through four sensitivity analyses, varying on the dataset or the clustering method.

RESULTS

A total of 16 drugs and 65 ADRs were included. Gabapentinoids were in Cluster #1, which included eight other drugs (isradipine, nicardipine, lacidipine, lercanidipine, ethosuximide, levetiracetam, zonisamide and nimodipine). Cluster #2 contained two drugs (diltiazem and verapamil) and Cluster #3 contained four drugs (amlodipine, felodipine, nifedipine and nitrendipine). The clustering results were consistent in all sensitivity analyses.

CONCLUSIONS

The safety profile of gabapentinoids overlaps with those of some dihydropyridine CCBs and Cav -blocking anticonvulsants. These results could be used to anticipate some unidentified ADRs of gabapentinoids from information accumulated with older drugs and sharing a common molecular target and ADR signature.

Rise of Pregabalin Poisoning and Abuse Cases in Serbia: A Ten-Year Retrospective Study

Purpose

The aim of this study was to analyze data on gabapentinoid-related attendances to the National Poison Control Center of Serbia (NPCC), particularly abuse cases; to estimate its changes and to compare it with trends in national consumption rates of these drugs. We also aimed to analyze the main characteristics of the study population and to investigate the major clinical effects in poisoned patients.

Patients and Methods

This is a retrospective study of patients admitted to the NPCC for acute poisoning involving gabapentinoids from 1 May 2012 to 1 October 2022.

Results

There were 357 (95.5%) pregabalin-related and 17 (4.5%) gabapentin-related poisoning cases in 302 patients. Abuse of pregabalin was detected in 27.8% (84/302), while gabapentin abuse occurred in 0.7% (2/302) of all patients. A steady increase in rates of pregabalin poisoning and abuse cases strongly correlated with the increase in overall consumption of this drug, while there were no significant changes in rates of gabapentin consumption, poisoning and abuse rate during the study period. Most patients who abused pregabalin pregabalin were males (84.5%) and the median age was 26 years (range: 15-45 years). Almost 60% of patients who abused pregabalin (48/84) belonged to the migrant population. Co-ingestions occurred in 89.4% of pregabalin-related cases (319/357), resulting in more severe poisoning. The most often co-ingested drugs were benzodiazepines and among them clonazepam was detected in the largest number of cases.

Conclusion

The poisoning and abuse cases involving pregabalin are on the rise in Serbia, which coincided with an increase in its overall consumption during the study period. Isolated pregabalin ingestions resulted in mild poisoning, although severe symptoms such as coma and bradycardia were recorded. When prescribing pregabalin to patients at risk of abuse caution is needed. Strengthening the measures for dispensing of pregabalin may reduce the risks associated with its abuse.

Gabapentinoid-induced peripheral edema and acute heart failure: A translational study combining pharmacovigilance data and in vitro animal experiments

INTRODUCTION

Gabapentinoids are ligands of the α2-δ subunit of voltage-gated calcium channels (Cav) that have been associated with a risk of peripheral edema and acute heart failure in connection with a potentially dual mechanism, vascular and cardiac.

OBJECTIVES & METHODS

All cases of peripheral edema or heart failure involving gabapentin or pregabalin reported to the French Pharmacovigilance Centers between January 1, 1994 and April 30, 2020 were included to describe their onset patterns (e.g., time to onset). Based on these data, we investigated the impact of gabapentinoids on the myogenic tone of rat third-order mesenteric arteries and on the electrophysiological properties of rat ventricular cardiomyocytes.

RESULTS

A total of 58 reports were included (gabapentin n = 5, pregabalin n = 53). The female-to-male ratio was 4:1 and the median age was 77 years (IQR 57-85, range 32-95). The median time to onset were 23 days (IQR 10-54) and 17 days (IQR 3-30) for non-cardiogenic edema and acute heart failure, respectively. Cardiogenic and non-cardiogenic peripheral edema occurred frequently after a dose escalation (27/45, 60%), and the course was rapidly favorable after discontinuation of gabapentinoid (median 7 days, IQR 5-13). On rat mesenteric arteries, gabapentinoids significantly decreased the myogenic tone to the same extent as verapamil and nifedipine. Acute application of gabapentinoids had no significant effect on Ca_v1.2 currents of ventricular cardiomyocytes.

CONCLUSION

Gabapentinoids can cause concentration-dependent peripheral edema of early onset. The primary mechanism of non-cardiogenic peripheral edema is vasodilatory edema secondary to altered myogenic tone, independent of Ca_v1.2 blockade under the experimental conditions tested.

Cardiac adverse effects of antiseizure medications

INTRODUCTION

Patients with severe epilepsy are at increased risk of cardiovascular disease and arrhythmias. Although antiseizure medications (ASMs) may have indirect protective effects against cardiovascular events by reducing seizure frequency and hence sudden death in epilepsy, some of them exert cardiotoxic effects.

AREAS COVERED

Patients with epilepsy, mainly those with severe forms, are at higher risk of cardiac disease because their heart can have structural alterations and electrical instability as a consequence of repeated seizures. Some ASMs have direct protective effects through anti-inflammatory, antioxidant, hypotensive, and lipid-reducing properties. Antiseizure medications can also have toxic cardiac effects including both long-term consequences, such as the increased risk of atherogenesis and subsequent cardiovascular disease due to the influence on lipid profile and pro-inflammatory milieu, and immediate effects as the increased risk of potentially fatal arrhythmias due to the influence on ion channels. Sodium channel blocking ASMs may also affect cardiac sodium channels and this effect is particularly observed in subjects with genetic mutations in cardiac ion channels. Fenfluramine cause valvulopathies in obese subjects and this effect need to be evaluated in epilepsy patients.

EXPERT OPINION

For the selection of treatment, cardiotoxic effects of ASMs should be considered; cardiac monitoring of treatment is advisable.

Comorbidity between epilepsy and cardiac arrhythmias: Implication for treatment

Epilepsy is often comorbid with either neurological or nonneurological diseases. The association between epilepsy and cardiac arrhythmias is not infrequent, mostly in patients with severe forms of epilepsy or critically ill. Remarkably, these medical conditions share many similarities. Vascular and genetic disorders may predispose to both seizures and abnormalities of cardiac electrophysiology. Repeated and uncontrolled seizures may favor potentially life-threatening arrhythmias. Antiepileptic drugs (AEDs) may facilitate the occurrence of cardiac arrhythmias by acting on ionic channels at heart level. Antiarrhythmic drugs (AADs) can have effects on ionic channels expressed in the brain, as suggested by their efficacy in treating patients with rare forms of epilepsy; AADs may also be proconvulsant, mainly during their overdosage. In clinical practice, the AEDs with the lowest risk to influence cardiac electrophysiology are to be preferred in patients presenting with either seizures or arrhythmias. Traditional AEDs should be avoided because of their arrhythmogenic properties and enzyme-inducing effects, which may make ineffective the concomitant treatment with AADs. Some of the newer AEDs can rarely affect cardiac rhythm, and electrocardiogram (ECG) monitoring should be warranted.