36-Year-Old Man With Persistent Erection

A 36-year-old white man with developmental delay presented to the primary care clinic for evaluation of a persistent erection of at least 8 hours' duration. He was nonverbal but appeared uncomfortable to his caregivers. There were no known urinary symptoms, perineal trauma, urological procedures, or previous episodes of similar symptoms. His medical history was notable for seizure disorder, hypothyroidism, and hyperlipidemia. Medications included phenobarbital, levothyroxine, simvastatin, and a multivitamin. No new medications had been initiated recently.On physical examination, he appeared to be in pain with his knees drawn to his chest. Vital signs were within normal limits. Genital examination revealed a tender, erect penis with rigid corpora cavernosa and bilateral descended testes. The glans penis was soft. There were no signs of trauma, urethral discharge, pelvic lymphadenopathy, or rash.