The pattern of adverse drug events to antiepileptic drugs: A cross-sectional study at a tertiary care teaching hospital

Abstract

Background: The goal of antiepileptic therapy is to achieve complete seizure control with minimum adverse effects impacting negatively on the quality of life. The drugs available in the market for the treatment of epilepsy have their own new and unique adverse drug reaction profile. Aims and Objective: To study the pattern of adverse drug events (ADEs) to antiepileptic drugs (AEDs) in a tertiary care teaching rural hospital in India. Materials and Methods: Data of all the patients visited the Outpatient Department of Neuromedicine, Neurosurgery, and Paediatric Department of the Shree Krishna Hospital in the study duration and who received AEDs as treatment, irrespective of diagnosis, age or sex were collected after obtaining written informed consent from the patients. All the adverse events reported spontaneously as well as founded by researcher during the interview at each visit were recorded in the case record form with all necessary information. Results: Total 112 ADEs were reported from 58 (36.25%) patients in 6-month follow-up. Central nervous system was most frequently affected with 68 (60.71%) ADEs followed by the gastrointestinal system (68, 60.71%). Phenytoin was most commonly suspected AEDs (with 39 cases) followed by carbamazepine (in 23 cases). Causality assessment by the WHO-UMC criteria most common association was possible in 75 (66.96%) cases, probable 21 (18.75%), certain 6 (5.36%), and conditional/unclassified 10 (8.93%). Similar result was obtained by Naranjo’s criteria as possible 84 (75.00%), probable 22 (19.64%), and definite 6 (5.36%). 91 (80.36%) ADEs were not preventable by modified Schumock and Thornton scale. Severity assessment by Hartwig’s criteria showed 79 (70.53%) ADEs as mild. Number of AEDs given per patient had a statistical correlation with ADEs. Conclusions: There are higher chances of development of ADEs in patients taking AEDs. However, at individualized regimens, the burden of ADEs is likely to be related more to individual responsiveness, type of AEDs/AED combinations chosen, and physician treatment skills, intensive therapeutic surveillance, education about epilepsy and the importance of drug compliance, and psychosocial interventions.