Contribution of methotrexate in precipitation of manic episode in bipolar affective disorder explored: a case report.

Bipolar affective disorder is characterized by recurring episodes of mania with or without, but commonly with, episodes of depression. It usually begins in adolescence and can cause enduring and substantial impairment if left untreated. It needs a long-term treatment with mood stabilizers to prevent relapses. Elevated or depressed mood relapses can be either primary or secondary. However, primary mood relapses can occur without a significant precipitating factor, more often tending to occur following stressful life events or discontinuation of mood stabilizer medications. Secondary mood relapses can be caused by many conditions, such as physical illnesses, substance misuse and medications. When a mental illness coexists with another physical illness and the treatment of one complicates the other, it adds complexity to the selection of appropriate pharmacological regime for either condition. In this paper, the authors present a case of bipolar affective disorder who had two episodes of mania likely precipitated by methotrexate, which were reversed by the withdrawal of the offending drug (methotrexate). To the best of the authors' knowledge, to date there have been no published reports in the literature in which methotrexate, an immunosuppressive and a cytotoxic drug, precipitated a manic episode in a patient with bipolar affective disorder.