Comparison between zimelidine and desipramine in endogenous depression. A cross-over study

Depressed patients, who did not respond after 4 weeks treatment with zimelidine 100 mg b.i.d. (five patients) or desipramine 75 mg b.i.d. (11 patients) in a double-blind randomized study were crossed over, after 1 placebo week, to 4 weeks of treatment with the other drug. The three zimelidine non-responders who responded to desipramine were significantly more retarded compared with eight desipramine non-responders who responded to zimelidine. It was observed that two patients with bipolar depression developed mania during crossover treatment with desipramine, while two patients with bipolar depression who were treated with zimelidine during the second treatment period did not show any symptoms of mania. Three patients who were non-responders during both treatment periods had lower plasma concentration of the drugs compared with respective responding groups.