Who should not take Viagra?

• Men who are currently using medicines that contain nitrates, such as nitroglycerin should not use Viagra because taken together they can lower the blood pressure too much.
• Viagra should not be used by women or children.

Reports of Patients’ Experiences Since Viagra Became Available:

In patients taking Viagra, several heart-related side effects have been reported, including heart attack, sudden death, irregular heart rhythm, stroke, chest pain, and increased blood pressure. It is not possible to determine whether these events are directly related to Viagra, to sexual activity, to the patient’s heart condition, to a combination of these factors, or to other factors.

The following factors are associated with increased blood levels of Viagra: 

• age greater than 65 years
• liver problems (such as cirrhosis)
• severe kidney problems
• taking certain medications at the same time (e.g., ketoconazole, itraconazole, erythromycin and saquinavir).

In these patients, the recommended starting dose of Viagra is 25 mg.

Special Warnings:

• Viagra was not studied in patients who have a history of the following conditions:
• Heart attack, stroke, or life-threatening irregular heart rhythm within the last 6 months
• Very low and very high blood pressure
• Heart failure or unstable chest pain
• Certain eye disorders
• Because Viagra lowers blood pressure, your doctor will evaluate your overall medical condition to determine if Viagra, in combination with sexual activity, could adversely affect you.
• Viagra can cause a rare but serious condition of prolonged erection (priapism). It is important to contact your health care provider immediately if your erection lasts longer than 4 hours.
• Men for whom sexual activity is inadvisable may not be good candidates for Viagra.
• Tell your doctor if you are taking protease inhibitors for the treatment of HIV.

General Precautions with Viagra: 

• You should have a complete medical history and exam to determine the cause of your impotence before taking Viagra.
• Men who have medical conditions that may cause a sustained erection such as sickle cell anemia, leukemia or multiple myeloma or who have an abnormally shaped penis may not be able to take Viagra.
• There are several medications that are known to interact with Viagra, so be sure to tell your doctor about all medications you are taking including those you can get without a prescription.
• Viagra has not been studied with other treatments for impotence, so use in combination with other treatments is not recommended.

What are some possible side effects of Viagra? (This list is NOT a complete list of side effects reported with Viagra. Your health care provider can discuss with you a more complete list of side effects.) (See "Reports of Patients’ Experiences Since Viagra Became Available " for additional information). The following is a listing of the most common side effects:

• Headache
• Flushing
• Upset stomach
• Stuffy nose
• Urinary tract infection
• Visual changes such as mild and temporary changes in blue/green colors or increased sensitivity to light.
• Diarrhea

For more detailed information about Viagra, ask your health care provider.

Link to Viagra's approved label 

Back to Entry Page

Updated: 12/2/98, 11/29/99
Revised: 7/25/00