The efficacy of lithium carbonate as a treatment for manic-depressive illness has stimulated a re-evaluation of the syndrome. In this paper, the authors review

the obstacles to timely diagnosis of manic-depressive illness in the adolescent. Three cases are presented demonstrating the usefulness of a unitary concept in which manic-depressive illness is understood and appreciated as having a physiologic basis, manifesting its effects in the total body system. The heretofore diverse and confusing psychological and behavioral symptoms of manic-depressive illness in adolescents become intelligible when regarded as secondary phenomena: the psychic experience of the process as filtered through the physicological constitution of the individual adolescent.