Treatment of bipolar depression.

Antidepressants have insufficient effect in 20-40% of patients treated for depressive disorders. This is particularly true for psychotic and agitated depression. When administered on a long-term basis, antidepressants cause a switch into mania in 25-40% of patients and induce rapid cycling. Classical antipsychotics have exhibited good therapeutic efficacy in the treatment of various forms of depression, especially psychotic and agitated forms, albeit burdened with many, above all extrapyramidal, side effects. When administered over long periods of time, classical antipsychotics may have a depressogenic effect. Second-generation antipsychotics have started to be increasingly used in this indication for a variety of reasons including: their antidepressant effect attributable to raised concentrations of catecholamines in the prefrontal cortex, their impact on serotonin transmission, their antipsychotic effect due to their mode of action including the mesolimbic blockade of dopamine D2 receptors, and the low incidence of extrapyramidal and other side effects. The following text encompasses the results of controlled trials using second-generation antipsychotics in the treatment of acute depressive disorders.