Complaints associated with the use of antiepileptic drugs: results from a community-based study

BACKGROUND Few data exist with respect to the occurrence of chronic side effects due to antiepileptic drugs (AED) in routine clinical practice. OBJECTIVE To evaluate the prevalence of subjective complaints which patients with epilepsy regard as side effects of their AED treatment in a community-based population. METHODS Cross-sectional study. Subjects were identified through the database of AED-use in the pharmacies in a suburban area in The Netherlands. Respondents completed a brief questionnaire about their epilepsy, including a checklist with 30 complaints, which are common in AED users. RESULTS We present data of 346 responding adults with treated epilepsy from a population of 107,000 adult inhabitants. Eighty percent was using monotherapy, with few patients taking new AEDs. Almost 60% of the patients reported complaints probably due to side effects in at least three domains. General CNS-related side effects were reported most often; memory problems (21.4% of the patients) and fatigue (20.3%) were dominant. Polytherapy was associated with more side effects than monotherapy. We identified differences in profiles of complaints between valproate, carbamazepine and phenytoin monotherapy. Complaints were not substantially associated with ongoing seizures or other treatment factors. CONCLUSIONS The majority of patients taking AEDs for epilepsy think they have side effects form their drugs, even when seizures were in remission and when monotherapy was used. Our findings suggest a need to improve monitoring of complaints of side effects of AEDs and to explore the feasibility of interventions aimed at reduction of such complaints in everyday clinical practice.