A 24-year-old man comes to the emergency department due to a painful erection for the past 6 hours. He has never had this condition before and says it is unrelated to sexual excitement. Medical history is significant for treatment-resistant major depressive disorder, obsessive-compulsive disorder, and insomnia. The patient has smoked a pack of cigarettes a day for 2 years and drinks 1 or 2 cans of beer daily. Examination reveals engorged corpora cavernosa but otherwise shows no abnormalities. Which of the following drugs is the most likely cause of this patient's condition?

Question

A 24-year-old man comes to the emergency department due to a painful erection for the past 6 hours.  He has never had this condition before and says it is unrelated to sexual excitement.  Medical history is significant for treatment-resistant major depressive disorder, obsessive-compulsive disorder, and insomnia.  The patient has smoked a pack of cigarettes a day for 2 years and drinks 1 or 2 cans of beer daily.  Examination reveals engorged corpora cavernosa but otherwise shows no abnormalities.  Which of the following drugs is the most likely cause of this patient's condition?

Quizplus · Accepted Answer

Trazodone is a sedating antidepressant used off-label most often as a hypnotic to treat insomnia associated with depression or antidepressant treatment. It has been associated with the rare but serious side effect of priapism (ie, persistent erection of the penis for >4 hours that is not associated with sexual excitement). Priapism is a medical emergency that, if left untreated, can result in permanent damage to penile tissue and erectile dysfunction. Priapism occurs most often in young adult men. Trazodone is a serotonin modulator (it antagonizes postsynaptic serotonin receptors and inhibits serotonin reuptake) that has minimal effects on norepinephrine and dopamine. Additional properties include alpha-adrenergic blockade-which may account for the side effects of orthostatic hypotension and priapism-and histamine H1 receptor antagonism, which contributes to its sedating effect. Trazodone should be used with caution in patients with conditions that predispose to priapism (eg, sickle cell disease). (Choices A, B, and E) These antidepressants have not been associated with priapism. Bupropion is a dopamine-norepinephrine reuptake inhibitor that is not associated with sexual side effects and may reduce sexual side effects induced by selective serotonin reuptake inhibitors (SSRIs) when used as an adjunctive treatment. Citalopram and paroxetine, in contrast, are SSRIs that have been associated with high rates of sexual side effects (eg, decreased libido, anorgasmia, delayed ejaculation). (Choices C, D, and F) Clomipramine and imipramine are tricyclic antidepressants used as second-line therapy due to their higher side effect burden and risk for cardiotoxicity in overdose. Phenelzine is a monoamine oxidase inhibitor used in the treatment of resistant depression; it requires dietary restrictions due to the risk of hypertensive crisis. These agents do not typically cause priapism. (Choice H) Zolpidem is a nonbenzodiazepine hypnotic used in the treatment of insomnia; it does not carry a risk of priapism. Educational objective: Trazodone is a highly sedating antidepressant commonly used to treat insomnia. Priapism is a rare but serious adverse effect. __________ References: Off-label trazodone prescription: evidence, benefits and risks. (http://www.ncbi.nlm.nih.gov/pubmed/26088119) Trazodone for insomnia: a systematic review. (http://www.ncbi.nlm.nih.gov/pubmed/29552421)

A 24-Year-Old Man Comes to the Emergency Department Due to a Painful