[Transition from the depressive stage to the manic stage during the treatment with antidepressive drugs]

The effects of antidepressant drugs on phase switching was studied in 602 individuals treated for endogenous depression. Altogether 869 depressed phases were evaluated retrospectively--there were 470 depressed phases in the course of bipolar affective disorder and 399 of unipolar disorder or with the undefined course. Switching from depression to mania was observed in patients with bipolar disorder--in 27.9% of cases of bipolar depression and in 21.5% of bipolar patients. Most frequently the switching was observed during management of depressed phase with amitriptyline (24.4% of treatments with this drug). The results point to a role of cholinergic system in pathophysiology of switching out of depression into mania during treatment with antidepressant drug.