Priapism associated with risperidone treatment.

Priapism is the occurrence of sustained and painful erection that does not result from sexual desire and fails to subside despite orgasm. It is often accompanied by pain and tenderness. The aetiologies are idiopathic, alcohol abuse, drug therapy, perinatal trauma and sickle-cell anaemia. It is a very rare adverse effect of psychotropic medications, due to alphaadrenergic receptor blockade. Priapism is reported in a 19-year-old physically healthy mental patient after 4 days of risperidone treatment 2 mg/day. ( Int J Psych Clin Pract 2000; 4: 237 - 239).