What medications increase the risk of priapism (prolonged erection)?

From the Guidelines

Medications such as antipsychotics, antidepressants, blood pressure medications, anticoagulants, and erectile dysfunction medications can increase the risk of priapism, a prolonged and often painful erection not related to sexual stimulation.

Key Points to Consider

• The mechanism typically involves these substances interfering with normal blood flow regulation in penile tissues, either by promoting excessive inflow or preventing outflow of blood 1.
• If you experience an erection lasting longer than four hours, seek immediate medical attention as priapism is a medical emergency that can lead to permanent tissue damage if not treated promptly 1.
• Patients with conditions like sickle cell disease or leukemia should be particularly cautious with these medications as they already have an elevated risk of priapism 1.
• Always inform your healthcare provider about all medications you're taking to assess potential risks 1.

Management of Priapism

• In patients presenting with a prolonged erection of four hours or less following intracavernosal injection pharmacotherapy for erectile dysfunction, clinicians should administer intracavernosal phenylephrine as the initial treatment option 1.
• Men with prolonged erections that are not fully rigid are less likely to later progress to acute ischemic priapism compared to those with fully rigid erections 1.
• The specific medication used to achieve the erection is an important factor to consider, with men treated with alprostadil alone being less prone to progress to ischemic priapism compared to those treated with papaverine and phentolamine 1.

From the FDA Drug Label

Cases of priapism (painful erections greater than 6 hours in duration) have been reported in men receiving Trazodone Hydrochloride Tablets. There have been rare reports of prolonged erections greater than 4 hours and priapism (painful erections greater than 6 hours in duration) for this class of compounds.

Medication Increase Risk of Priapism:

• Trazodone: Yes, trazodone increases the risk of priapism, as reported in the drug label 2.
• Tadalafil: Yes, tadalafil also increases the risk of priapism, as reported in the drug label 3. Key Points:
• Priapism can result in irreversible damage to the erectile tissue if not treated promptly.
• Patients should seek emergency medical attention if they experience an erection lasting greater than 4 hours.

From the Research

Medication-Induced Priapism

• Priapism is a persistent, painful, and prolonged penile erection that can be caused by various medications, including antipsychotics and trazodone 4, 5, 6, 7, 8.
• The mechanism of priapism associated with antipsychotics is thought to be related to alpha-adrenergic blockage in the corpora cavernosa of the penis 4, 5.
• Atypical antipsychotics, also known as second-generation antipsychotics, have been reported to cause priapism, although it is a rarely reported side effect 4, 5.
• Other medications that have been implicated in priapism include phenothiazines, prazosin, and heparin 6.
• Trazodone has been associated with priapism, particularly within the first 28 days of treatment and with doses of 150 mg/day or less 8.

Risk Factors and Treatment

• A past history of prolonged and painless erections is the best predictor for the subsequent development of priapism 5.
• Clinicians should educate patients treated with antipsychotics and other medications that can cause priapism about the potential for this side effect and its sequelae, including permanent erectile dysfunction 4, 5.
• Priapism is a urological emergency that requires prompt treatment to prevent long-term complications, such as erectile dysfunction 4, 5, 6.
• Treatment options for priapism include surgical procedures and drug treatment, although the exact approach depends on the individual case 6, 7.