[Response to serotonergic and noradrenergic antidepressants: a crossover study of fluoxetine and desipramine in patients with first major depression episode].

Background: Response rate data from studies with different kinds of antidepressant drugs help in the development of guidelines for the rational prescription of pharmacotherapy. However, there are still few comparative studies with selective reuptake inhibition on serotonin or norepinephrine in the same sample of major depression patients.

Methods: First episode major depression (DSM-III-R) outpatients who completed 6 weeks in two double-blind randomized trials with fluoxetine and desipramine were crossed over to treatment with the other drug under open conditions for 6 weeks. Response was considered if patient's final Hamilton depression scale score decreased 50% or more from baseline.

Results: No significant differences were found by drug treatment or sequence of treatment. Ten of the 18 patients (55.5%) were responders to both fluoxetine and desipramine, 3 (16.6%) were resistant to fluoxetine, 3 (16.6%) to desipramine and 2 (11.1%) to both drugs.

Discussion: These data suggest that among first major depressive episode outpatients fluoxetine and desipramine are equally effective. In patients who have been non-responders to one of the studied drugs, the other one is strikingly effective; this kind of treatment maneuver should be considered in such patients.