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Get Answers to Questions



How long does it take for CAVERJECT IMPULSE to work?

After injection, you can expect an erection to occur within 5 to 20 minutes. Your erection should last no longer than an hour.

How often can I use CAVERJECT IMPULSE?

CAVERJECT IMPULSE should be used no more than 3 times per week, with at least 24 hours between each use.

What is the most common side effect?

About 1 in 3 patients experienced mild to moderate pain after injection.

Can I travel with CAVERJECT IMPULSE?

Yes. You can take CAVERJECT IMPULSE with you when you are on the go via car, plane, or train. However, it is important to remember that unmixed packages of CAVERJECT IMPULSE should be stored at room temperature (59° F to 86° F). During travel, CAVERJECT IMPULSE should not be stored in checked luggage or left in a closed automobile that may get too cold (below 59° F) or too hot (above 86° F).

What should I do with the remaining medicine in the syringe after an injection?

CAVERJECT IMPULSE is for one use only and should be thrown away properly after a single use. Your dose has been selected for your individual needs. Do not change your dose for self-injection without consulting your doctor.

How do I dispose of CAVERJECT IMPULSE?

After use, dispose of all injection materials safely. Your pharmacist may be able to supply a disposal box especially for disposable injection delivery systems.

What should I do if I have an erection for more than 4 hours?

Some men who use CAVERJECT IMPULSE may get erections that last more than 4 hours. These can cause serious and permanent damage. Call your doctor or seek professional help immediately if you still have an erection 4 hours after injection.

Who should not use CAVERJECT IMPULSE?

Do not use CAVERJECT IMPULSE if you have certain conditions that might cause long-lasting erections (lasting more than 4 hours). Long-lasting erections may cause penis damage. These conditions include:

  • sickle cell anemia or trait
  • leukemia
  • tumor of the bone marrow (multiple myeloma)

Do not use CAVERJECT IMPULSE if you

  • have a penile implant
  • have an abnormally formed penis
  • have other penis problems
  • were told by your doctor not to have sex

Women and children should not use CAVERJECT IMPULSE.


Important Safety Information

Do not use CAVERJECT IMPULSE® (alprostadil for injection) if you have:

  • Certain medical problems that might cause you to have an erection that lasts for more than 4 hours, such as sickle cell anemia, sickle cell trait, multiple myeloma, or leukemia
  • A deformed penis shape
  • A penile implant

Women and children should not use CAVERJECT.

Before you use CAVERJECT IMPULSE, tell your healthcare provider if you:

  • Have had an erection that lasted more than 4 hours
  • Have sickle cell trait or sickle cell anemia
  • Have or have had a blood cell cancer called multiple myeloma or leukemia
  • Have a deformed penis shape
  • Have a penile implant
  • Have low blood pressure (hypotension)
  • Have bleeding problems
  • Have or have had heart problems such as a heart attack, irregular heartbeat, angina, chest pain, narrowing of the aortic valve or heart failure
  • Have any other medical conditions

Tell your healthcare provider about all the medicines you take, including prescription and over-the-counter medicines, vitamins, and herbal supplements. CAVERJECT IMPULSE may affect the way other medicines work, and other medicines may affect the way CAVERJECT IMPULSE works, causing side effects.

Especially tell your healthcare provider if you take any other medicines that are injected into your penis (intracavernosally) or certain medicines called anticoagulant medicines (such as heparin or warfarin).

CAVERJECT IMPULSE may cause serious side effects, including:

  • An erection that will not go away. If you have an erection that lasts more than 4 hours, get medical help right away. If it is not treated right away, this condition can permanently damage your penis.
  • Deformed penis shape (penile fibrosis). Your healthcare provider should check your penis regularly for signs of penile fibrosis. You should not continue to use CAVERJECT IMPULSE if you get penile fibrosis
  • Low blood pressure (hypotension)
  • Injection site bleeding. People who take certain medicines called anticoagulants (such as heparin or warfarin) may have a risk for increased bleeding at the injection site
  • Increased risk of heart problems. Sexual activity can put an extra strain on your heart, especially if your heart is weak from a heart attack or heart disease. Ask your healthcare provider if your heart is healthy enough to handle the extra strain of having sex. Stop sexual activity and immediately contact your healthcare provider for advice if you get symptoms of a heart problem such as chest pain, dizziness or nausea
  • Needle breakage. There is a possibility of needle breakage with use of CAVERJECT IMPULSE. To best avoid breaking the needle, you should pay careful attention to your healthcare provider’s instructions and try to handle the syringe and needle properly. If the needle breaks during injection and you are able to see and grasp the broken end, you should remove it and contact your healthcare provider. If you cannot see or cannot grasp the broken end, you should promptly contact your healthcare provider

CAVERJECT IMPULSE does not protect you or your partner from getting sexually transmitted infections, including HIV- the virus that causes AIDS.

The most common side effects of CAVERJECT IMPULSE include:

  • Penile pain
  • Erection lasting 4 to 6 hours (prolonged erection)
  • Penile fibrosis
  • Bruising at the injection site
  • Penile disorders such as numbness, irritation, sensitivity, itching, swelling, and discoloration, or skin-tears of the penis
  • Penile rash
  • Penile swelling

Tell your healthcare provider if you have any side effect that bothers you or does not go away.


CAVERJECT IMPULSE is a prescription medicine that is used to treat erectile dysfunction in adult men.

Patients should always ask their doctors for medical advice about adverse events.

You may report an adverse event related to Pfizer products by calling 1-800-438-1985 (US only). If you prefer, you may contact the U.S. Food and Drug Administration (FDA) directly. The FDA has established a reporting service known as MedWatch where health care professionals and consumers can report serious problems they suspect may be associated with the drugs and medical devices they prescribe, dispense, or use. Visit MedWatch or call 1-800-FDA-1088.

Please see full Prescribing Information, Patient Information, and Instructions for Use for CAVERJECT IMPULSE.

The health information contained herein is provided for educational purposes only and is not intended to replace discussions with a health care provider. All decisions regarding patient care must be made with a health care provider, considering the unique characteristics of the patient.

The product information provided in this website is intended only for residents of the United States. The products discussed herein may have different product labeling in different countries.