Effect of tricyclic antidepressants on switching to mania and on the onset of bipolarity in depressed 6- to 12-year-olds.

The authors present data on the rates of onset of bipolar phenomena, at 2- to 3-year follow-up, in depressed 6- to 12-year olds. The subjects had participated in the nortriptyline drug study. There were high rates of onset of bipolarity and of switching to mania while patients were on tricyclic antidepressants (TCAs). Mania developed only in subjects who had received TCAs at some time in the past or were receiving them concurrent with the onset of mania. These findings were analyzed with respect to the influence of multiple covariates, including family history of manic disorders and pubertal status. The authors discuss the implications of these findings for the prescription of TCAs to children who present with major depressive disorder and have a family history of bipolarity or a history of bipolar symptoms. The relevance of these findings for the later development of rapid cycling is discussed and compared with predictors of rapid cycling in adults.