Priapism (An Erection that Lasts Too Long)

This information describes what to do if you develop priapism (an erection that lasts too long).

Priapism can develop without sexual stimulation and doesn’t go away after ejaculation. There is a small risk of having priapism for 4 hours or more after penile injection therapy. When an erection is rigid, no fresh blood flows into the penis. This means the penis is not getting oxygen, which can damage the tissue and lead to permanent erectile dysfunction (ED). The only way to correct this condition is to have a penile implant.

If You Develop Priapism

  • If you have an erection that lasts 2 hours, take 4 (30 mg) tablets of pseudoephedrine HCl (Sudafed®). Do not take extended-release or long-acting tablets, such as Sudafed® 12 hour. Ask your pharmacist, doctor, or nurse if you have any questions.
    • You don’t need a prescription to buy this medication, but the boxes are kept behind the pharmacy counter. Take the pseudoephedrine HCl card that is hanging on the shelf to the pharmacist (see figure). You will have to show a photo ID and then the pharmacist will give you the box to purchase.
    • Make sure to have pseudoephedrine HCl with you as long as you are using the penile injections.
    • If you have problems with your heart, talk with your cardiologist about whether it’s safe for you to take pseudoephedrine HCl.
  • If you have an erection that lasts 3 hours (you still have an erection 1 hour after taking pseudoephedrine HCl), speak with your doctor nurse.
    •  On Mondays through Fridays from 9:00 am to 5:00 pm, call 646-888-6024.
    • After 5:00 pm, during the weekend, and on holidays, call 212-639-2000 and ask to speak to the urologist on call.
  • If you have an erection that lasts 4 hours and you haven’t talked to a doctor or nurse, this is a medical emergency. You should treat it with the same urgency as a heart attack. Erections lasting longer than 4 hours can cause permanent damage.
  • Go to MSK’s Urgent Care Center (1275 York Avenue) if you are less than 30 minutes away. Ask the guard at the entrance to the hospital how to get there.
  • Go to your local emergency room if you live more than 30 minutes away.
  • A doctor or nurse should see you immediately. If you are not treated quickly, you may have ED that will not get better.
  • Give the doctor or nurse the priapism card that was given to you to carry in your wallet. You can also have the doctor or nurse call us at the numbers listed above.

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