Psychotropic drug-induced priapism: Incidence, mechanism and management

Several psychotropic medications have been implicated in causing priapism. This adverse effect occurs infrequently and, although it can occur in females (i.e. clitoral priapism), has a male predominance. Psychotropic drug-induced priapism does not appear to be dose-dependent nor does it appear to correlate with the duration of treatment. To date, the most widely accepted mechanism of this effect involves a relative decrease in local sympathetic tone with respect to the local parasympathetic tone. The significance of priapism lies in the potential for the development of damaging ischaemic penile fibrosis and subsequent impotence. Prompt treatment. within 4 to 6 hours of onset, has been demonstrated to reduce morbidity and decrease the need for surgical intervention. Treatment recommendations for psychotropic drug-induced priapism include penile aspiration, irrigation, instillation of vasoactive agents and, if necessary, shunting procedures. Perhaps the most important consideration is patient education with respect to this potentially damaging adverse drug effect. Patients should seek prompt medical attention if a prolonged erection occurs. An inquiry should be made to determine if the patient has a history of prolonged erections, as this finding is present in approximately 50% of subsequent cases of psychotropic drug-induced priapism.