Priapism (An Erection that Lasts Too Long)

Time to Read: About 2 minutes

This information describes what to do if you develop priapism.

About Priapism

Priapism is an erection that lasts too long. Priapism can develop without sexual stimulation and doesn’t go away after orgasm. There is a risk of having priapism after penile injection therapy.

When you have a full erection, no fresh blood flows into your penis. This means that your penis isn’t getting oxygen, which can damage the tissue and lead to permanent erectile dysfunction (ED).

About Pseudoephedrine HCl (Sudafed®)

Figure 1. Pseudoephedrine HCl (Sudafed)
Figure 1. Pseudoephedrine HCl (Sudafed)

If you have priapism, taking pseudoephedrine HCl (Sudafed®) can help. You can buy pseudoephedrine HCl at your local pharmacy without a prescription, but the boxes are kept behind the pharmacy counter.

To buy pseudoephedrine HCL, take the pseudoephedrine HCl card that’s hanging on the shelf to the pharmacist (see Figure 1). You will have to show a photo ID before the pharmacist gives you the box to purchase. Do not purchase pseudoephedrine HCL that’s on the shelf. This is phenylephrine and is not the appropriate medication to use for priapism.

If you have problems with your heart, talk with your cardiologist about whether it’s safe for you to take pseudoephedrine HCl.

If you’re taking penile injections, make sure to have pseudoephredrine HCl with you as long as you’re using the injections.

If You Develop Priapism

  • If you have an erection at penetration hardness (a 6 or higher on the erection hardness scale) that lasts 2 hours, take 4 (30 mg) tablets of pseudoephedrine HCl (Sudafed). Don’t take extended-release or long-acting tablets, such as Sudafed 12 hour. Ask your pharmacist or Advanced Practice Provider (APP) if you have any questions. The pseudoephedrine HCl will be shipped by the compounding pharmacy along with the vial of medication and syringes, or you can buy it at your local pharmacy.
    • If your erection becomes less than penetration hardness within an hour of taking pseudoephedrine HCl, call your healthcare provider’s office the next day to speak with your APP. You shouldn’t continue to inject with the same dose if you took pseudoephedrine HCl for a prolonged erection. Your APP will make changes to your penile injection therapy medication dose. Do not inject again until you speak to your healthcare provider.
  • If you have an erection that lasts 3 hours (you still have an erection 1 hour after taking the pseudoephedrine HCl), call your APP.
    • Monday through Friday between and , call your APP.
    • Between and , during the weekend, and on holidays, call 212-639-2000 and ask to speak to the urologist on call.
    • Go to MSK’s Urgent Care Center at Memorial Hospital (1275 York Avenue, between East 67th and East 68th Streets) if you’re less than 30 minutes away. Your APP will call the Urgent Care Center so they know to expect you. Your APP will give you more instructions during your call.
  • If you have an erection that lasts 4 hours and you haven’t talked to your APP, 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 to your erection tissue.
    • Go to MSK’s Urgent Care Center if you’re 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’re more than 30 minutes away from Memorial Hospital.
    • Tell the staff at the Urgent Care Center or emergency room that you’ve had an erection for 4 hours. A healthcare provider should see you immediately. If you aren’t treated quickly, it’s possible that you will end up with permanent ED.
    • Give the healthcare provider the priapism card that was given to you to carry in your wallet. You can also have the healthcare provider call us at the numbers listed above.

Last Updated

Thursday, May 6, 2021

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