Despite the increasing use of many new antiepileptic drugs (AEDs) with differing mechanisms of action, our previous study demonstrated overall unchanged seizure outcome in newly diagnosed epilepsy over the past two decades. However, the long-term tolerability profile of AED therapy is not well studied. Here, we analyzed the profile of AED-induced adverse drug reactions (ADRs) over a 30-year period.
Adults who were newly treated with AEDs at the Epilepsy Unit of the Western Infirmary in Glasgow, Scotland between 1 July 1982 and 31 October 2012 were included. All patients were prospectively followed till 30 April 2016 or death. ADRs reported by the patients were systematically reviewed and categorized into Medical Dictionary for Regulatory Activities. ADRs that led to the discontinuation of the AED were defined as intolerable.
One-third of patients had discontinued AEDs due to ADRs. Overall, the established and newer AEDs had same tolerability rate. Number of concomitant AEDs significantly reduced tolerability. A history of intolerable ADR had great impact on the tolerability of future regimens. Patients tended to have better tolerance to AED over the course of treatment if no previous intolerable ADR or no concomitant AED was introduced.