Volume :
6
Issue :
2
Abstract :
Introduction
Neurological disorders have been estimated to account for up to 20% of the nationwide cost of healthcare in developed countries. There is growing concern to assess the Adverse Drug Reactions (ADRs) of anti-epileptic drugs (AEDs), which have an impact on compliance, economic burden and quality of life. AEDs have broad spectrum of effects, need long term therapy leading to wide range of ADRs. Thus, the present study was undertaken.
Aim
To assess the incidence, severity, causality of ADRs due to AEDs and to compare the pattern of ADRs caused by conventional versus newer AEDs.
Methodology
This observational study was carried out from 2012 to 2016 to analyze the ADRs reported spontaneously from Department of Neurology at Bangalore Medical College and Research Institute to ADR monitoring centre. Patient demographics, clinical & drug data, details of ADR, onset time, causal drug details, outcome and severity were collected as per CDSCO ADR reporting form. Causality was assessed using WHO-ADR probability scale, preventability by Modified Schumock & Thornton scale and severity using Hartwig and Siegel Scale. Predictability was categorized as Type A and Type B ADRs.
Results
85 ADRs were reported in 5 years, with maximum in 21-40 yrs and equal male to female ratio. Conventional AEDs (75%), mainly Phenytoin (40%) and Carbamazepine (27%) contributed the most. Amongst newer AEDs, Levetiractam accounted for maximum ADRs (13%) followed by Gabapentin (10%). ADRs affecting Central Nervous System (CNS) (65%) were predominant in both groups. Newer AEDs caused Giddiness 10.7 times more frequently than conventional ones. Erythematous rash was 1.71 times more in the conventional drugs than newer ones. Frequency of drug withdrawal was higher among the patients on conventional AEDs (60% vs 30%). Causality assessment indicated that 90% had probable and 10% had possible causality. Majority of the ADRs in both the groups were of moderate severity (50%). The severe ADRs (7%) seen only with conventional AEDs were hepatotoxicity & pancreatitis due to Sodium Valproate and hyponatraemia due to Carbamazepine. Definitely preventable ADRs (12%) were noted among both the groups. No mortality was reported.
Conclusion
85 ADRs due to AEDs were reported in 5 years period. Among conventional AEDs, Phenytoin and Carbamazepine contributed the maximum. Amongst newer AEDs, Levetiractam, followed by Gabapentin were implicated in majority of ADRs. ADRs affecting CNS were predominant in both groups. Severe ADRs were seen with only conventional AEDs.