Examination and treatment of sleep-related painful erections--a case report.

The case of a patient with sleep-related painful erections is described. Insomnia and a slight depressive syndrome occurred along with a long history of this disorder. No physical abnormality was found. At a baseline recording of sleep electroencephalography (EEG) and nocturnal penile tumescence (NPT), a disturbed sleep pattern and impaired NPT were recorded. Attempts to treat the disorder with diazepam, amitriptyline, trimipramine, and biperidene did not prompt a stable improvement of the disorder, but a dosage of 25 mg clozapine was sufficient to achieve normalized sleep architecture, remission of the depressive symptomatology, and normalization of NPT. It is likely that marked sedation is the mode of action of clozapine.