[Convulsions observed during administration of antidepressants]

We investigated the incidence of convulsions observed during treatment with antidepressants. Among the patients observed in this department, 582 cases received the antidepressants for more than 2 months were selected. 8 cases (1. 4%) of these patients showed convulsions. Detailed evaluation revealed a high incidence of convulsions occurred in patients who were administered more than two kinds of antidepressants. Among tetracyclic antidepressants, viz. maprotiline and clomipamine, and tricyclic antidepressants, viz. amitriptyline indicated a high incidence rate of convulsions. On the contrary, mianserin and imipramine tended to show a lower incidence. In 4 cases, acute toxic symptoms were seen before the convulsion, and the serum concentration of antidepressants in these patients was high. If toxic symptoms and elevated level of serum concentration are useful indicator for prediction of convulsion by treatment with antidepressants, these might be a noteworthy clinical findings. At present, if doctors are required to administer more than moderate amounts of more than two antidepressants, careful administration is desirable. With the accumulation of such cases, it is necessary to obtain further evaluation of the relationship between toxic symptoms and serum concentration of antidepressants.