Late-onset Bipolar I Disorder.

Bipolar I disorder is a chronic psychiatric illness in which patients alternate between symptoms of both mania and depression. Most cases are diagnosed when patients are 20 to 50 years old. We describe a patient presenting with symptoms of acute mania at an unusually late age for this condition. After a workup for an organic etiology, including imaging studies, this 71-year-old man was diagnosed with bipolar I disorder. Since diagnosis, his condition has been managed with risperidone.