Bipolar affective disorder in aged patients.

Bipolar affective illness may be a relatively common missed diagnosis in the elderly. Inaccurate historical data, atypical course of illness and atypical clinical presentation are all sources of diagnostic error. Lithium and tricyclic antidepressants are effective agents in this age group but require close monitoring, with particular attention to their interaction with illness and other medications. A high index of suspicion for bipolar illness is suggested when elderly patients present with depression.