Priapism and risperidone.

A patient taking oral risperidone while using cocaine and alcohol presented with priapism shortly after long-acting, injectable risperidone was prescribed. Another case of priapism was diagnosed in a sickle cell disease patient who was on oral risperidone. A penectomy due to necrosis was required in the first case, while the other patient regained erectile function. Physicians should be aware of priapism-inducing/predisposing factors, such as sickle cell disease, certain medicines or drugs of abuse, and antipsychotic medications. Risperidone is an established cause of priapism. It occurs especially in males with sickle cell disease; use of antipsychotic drugs and/or cocaine further increases risk.