Severe adverse drug reactions of antidepressants: Results of the German Multicenter Drug Surveillance Program AMSP

The drug safety program in psychiatry „AMSP“ („Arzneimittelsicherheit in der Psychiatrie“) is a hospital-based independent system of pharmacovigilance. It is reported on 53.042 of 122.562 patients treated with antidepressants who were monitored from the year 1993 through 2000 in 35 psychiatric hospitals in German speaking countries. The overall incidence of severe ADRs of antidepressants was 1,4% of exposed patients; when only ADRs rated as probable or definite were considered, a rate of 0,9% was observed. ADR rates were higher for TCA and lower for MAO-inhibitors with ADRs due to SSRI ranging in between. Dual acting antidepressants venlafaxine and mirtazapine were recently included in our monitoring process; according to our data it remains unclear whether any specific SSRI or venlafaxine had a stronger association with the special risk of hyponatremia; but there is evidence that the risk of mirtazapine is lower.