Abstract

The antidepressant action of imipramine (Tofranil - Geigy) is probably due not to the direct action of the drug itself, but to one of its metabolites, desmethylimipramine (B. B. Brodie et al., Med. exp. 1961, 5, 454), which has been given the Approved Name desipramine. This substance is now marketed as Pertofran (Geigy). It has been suggested but not proved that imipramine takes several weeks to work because this time-lag is necessary for the active metabolite to accumulate. If this is true, desipramine might be expected to act more quickly than imipramine in the treatment of depressive illness.