Alprostadil is a medication that healthcare providers most commonly prescribe to treat erectile dysfunction. There are two main types: a solution that you inject directly into your penis and a suppository that you insert into your urethra. Side effects aren’t common, but may include an allergic reaction, pain and bruising.


What is alprostadil?

Alprostadil is a type of vasodilator that healthcare providers most commonly prescribe to treat erectile dysfunction (ED or impotence). Vasodilators help increase blood flow through the blood vessels (arteries) by relaxing their walls and making them wider. Alprostadil is identical to a naturally occurring substance in your body that helps keep the blood vessels open.

You shouldn’t use alprostadil if you don’t have ED. It’s also unsafe to take more than your healthcare provider recommends. Improper use of alprostadil could cause permanent damage to your penis that prevents you from getting erections.

What is alprostadil used for?

Healthcare providers usually prescribe alprostadil to help treat ED by increasing blood flow inside your penis, which helps you maintain an erection. You take alprostadil before sexual activity.


Cleveland Clinic is a non-profit academic medical center. Advertising on our site helps support our mission. We do not endorse non-Cleveland Clinic products or services. Policy

Procedure Details

Is alprostadil right for me?

You might take alprostadil if pills to treat ED don’t work or cause side effects. This medication is considered the next step up in therapy.

Before taking alprostadil, tell your doctor if you:

How do I take alprostadil?

Alprostadil comes in two main forms:

Injectable alprostadil

You may inject alprostadil by itself or as a mix with other medications to increase its effectiveness. Names for the alprostadil mix may include Bimix, Trimix and Quadmix.

As a single ingredient, alprostadil comes in powder form. You must mix it with a liquid before you inject it into the side of the penis with a tiny needle.

It’s important to know that there isn’t one set dose for alprostadil. You may need to gradually adjust the dosage according to how your body responds. It may take some time to find the right dose. If a healthcare provider prescribes injectable alprostadil, they’ll teach you how to use it.

Where do you inject alprostadil?

You inject alprostadil into the side of your penis.

Transurethral alprostadil

Transurethral alprostadil is a type of suppository. You insert a tiny tablet or pellet into your urethra (the tube in your penis through which pee comes out of your body). It gradually breaks down inside your urethra and absorbs into your body.

Studies show that transurethral alprostadil is less effective. There’s also a greater association with pain in your penis and burning.


Is there an alprostadil topical cream?

Topical alprostadil comes in the form of a cream or gel. You apply it to the end of your penis before sexual intercourse. However, topical alprostadil doesn’t have United States Food and Drug Administration (FDA) approval. It isn’t available in the U.S. as of yet.

How often can I take alprostadil?

It’s important that you follow your alprostadil directions carefully. You shouldn’t use injectable alprostadil more than two to three times per week. You should wait at least 24 hours between each time you use it. Avoid using transurethral alprostadil more than twice every 24 hours.

How long does it take for alprostadil to work?

You should be able to get an erection within five to 20 minutes of taking injectable alprostadil. Transurethral alprostadil should start to work within 10 minutes.

How long will I need alprostadil?

It depends on your situation. Alprostadil isn’t a cure for erectile dysfunction. But when you use it correctly, it’s a safe, effective, long-term treatment for erectile dysfunction. Many people choose to use alprostadil for a long time.


Risks / Benefits

What are the potential benefits of alprostadil?

The primary benefit of alprostadil is that it helps you to get and maintain an erection firm enough to have sexual intercourse.

How effective is alprostadil?

Alprostadil is very effective. It causes an erection firm enough for sexual intercourse in about 80% of men and people assigned male at birth (AMAB).

What are the risks or complications of alprostadil?

Alprostadil complications aren’t common. But there are possible risks.

Transurethral alprostadil risks include:

Injectable alprostadil risks include:

  • Low blood pressure.
  • High blood pressure (hypertension).
  • A prolonged erection.
  • Skin rash on your penis.
  • Swelling of your penis.
  • Bruising around the injection site.
  • Headache.
  • Dizziness.

Very rarely, injectable alprostadil may also cause a penile infection.

Recovery and Outlook

How long does alprostadil last?

Your erection should last between 30 minutes and an hour. You may continue to have an erection after you orgasm, but it should go away within an hour.

When To Call the Doctor

When should I call a healthcare provider?

Contact a healthcare provider as soon as possible if:

  • You develop a painful curve when you have an erection.
  • Your erection lasts longer than two hours.
  • You have swelling or pain in your testicles, perineum or legs.
  • Veins in your legs start to swell.
  • You develop flu-like symptoms, including fever, chills or nausea and vomiting.
  • You feel dizzy or faint.
  • You develop scarring or hard areas on your penis.
  • The needle breaks during the injection.
  • The alprostadil solution looks cloudy, is a different color or has debris.

When should I go to the ER?

Go to the nearest emergency room if your erection lasts longer than four hours.

Additional Details

Can you take Viagra® and alprostadil together?

No, you shouldn’t combine alprostadil with other oral medications for ED. Taking alprostadil in combination with Viagra or other similar drugs may increase toxic effects.

The most common complication includes a prolonged erection that lasts longer than four hours. This requires treatment at an ER. Without proper treatment, it can cause permanent damage to your penile tissue.

What is the average cost of alprostadil?

The average cost of alprostadil is over $500 for a 5-milliliter (teaspoon size) vial. The cost per dose depends on how much you need to inject, which varies from person to person. The lower the volume that you need to inject, the more doses per vial you’ll get, which makes it cheaper per dose.

The cost of alprostadil may also depend on:

  • Your health insurance coverage.
  • What your provider charges.
  • The pharmacy where you pick up your prescription.

A note from Cleveland Clinic

Alprostadil can help treat erectile dysfunction and improve your sex life. ED can cause a lot of different feelings — frustration, embarrassment, shame and even humiliation. You may even experience these feelings when you seek help from a healthcare provider. But ED is common, and providers are available to help you and make you as comfortable as possible with your questions and concerns. Ask a provider if alprostadil is the best treatment for you or if another medication is better.

Medically Reviewed

Last reviewed on 07/31/2023.

Learn more about our editorial process.

Urology 216.444.5600
Kidney Medicine 216.444.6771