Pharmacovigilance in epileptic patients using antiepileptic drugs

To investigate the occurrence of adverse effects of antiepileptic drugs (AED) in chronic epileptic patients in mono or polytherapy.

We evaluated consecutive patients that met the following inclusion criteria: age of 18 years or older, diagnosis of epilepsy for at least one year, stable dose of AED for at least three months. Patients were asked if they had any adverse event related to the AED. After that, they were interviewed according to a detailed semi-structure questionnaire. We also assessed specifically the adverse events in the last four weeks. The data were analyzed regarding the use of monotherapy x polytherapy, and the presence of probable depression (score>15) according to the Center for Epidemiologic Studies Depression Scale.

Sixty-five patients were evaluated, 35 women, mean age 38.3 years; 35 patients were in use of monotherapy and 35 in polytherapy. Only 45 (69.2%) patients spontaneously reported adverse effects. After the formal questionnaire, 63 (97%) patients referred experiencing an adverse event (p<0.001). Seventeen men had adverse events, as opposed to 28 women (p=0.042). When the last four weeks were evaluated, patients with probable depression presented adverse events more frequently (p<0.0001).

Our data suggest that adverse events are highly prevalent when a detailed questionnaire is applied and that depression may aggravate the number and intensity of side effects in patients using AEDs.