Revatio relaxes muscles of the blood vessels and increases blood flow to particular areas of the body.

Revatio is used to treat pulmonary arterial hypertension and improve exercise capacity in men and women.

Sildenafil under the name Viagra is used to treat erectile dysfunction (impotence) in men.

Do not take Viagra while also taking Revatio, unless your doctor tells you to.

Do not take Revatio if you are also using a nitrate drug for chest pain or heart problems, including nitroglycerin, isosorbide dinitrate, isosorbide mononitrate, and some recreational drugs such as "poppers". Taking Revatio with a nitrate medicine can cause a sudden and serious decrease in blood pressure.

Some medicines can cause unwanted or dangerous effects when used with sildenafil. Tell your doctor about all your current medicines, especially riociguat (Adempas).

Stop using Revatio and get emergency medical help if you have sudden vision loss.

Take Revatio exactly as it was prescribed for you. Follow all directions on your prescription label and read all medication guides or instruction sheets.

Revatio is usually taken three times each day, about 4 to 6 hours apart.

Shake the oral suspension (liquid) before you measure a dose. Use the dosing syringe provided, or use a medicine dose-measuring device (not a kitchen spoon).

During sexual activity, if you become dizzy or nauseated, or have pain, numbness, or tingling in your chest, arms, neck, or jaw, stop and call your doctor right away. You could be having a serious side effect of Revatio.

Store at room temperature away from moisture and heat.

Usual Adult Dose for Pulmonary Hypertension:

Revatio:
Oral:
-Initial dose: 5 or 20 mg orally three times a day, 4 to 6 hours apart
-Maximum dose: 20 mg orally three times a day

Injection:
-Initial dose: 2.5 or 10 mg IV bolus three times a day

Comments:
-No greater efficacy was achieved with oral doses higher than the maximum recommended dose.
-A 10 mg injection dose is predicted to provide pharmacological effect equivalent to the 20 mg oral dose.

Use: Treatment of PAH (WHO Group I) in adults to improve exercise ability and delay clinical worsening

You should not use Revatio if you are allergic to sildenafil, or:

• if you take other medicines to treat pulmonary arterial hypertension, such as riociguat (Adempas).

Do not take sildenafil if you are also using a nitrate drug for chest pain or heart problems. This includes nitroglycerin, isosorbide dinitrate, and isosorbide mononitrate. Nitrates are also found in some recreational drugs such as amyl nitrate or nitrite ("poppers"). Taking sildenafil with a nitrate medicine can cause a sudden and serious decrease in blood pressure.

To make sure Revatio is safe for you, tell your doctor if you have ever had:

• heart problems (chest pain, a heart rhythm disorder, heart attack);

• high or low blood pressure;

• blood circulation problems;

• retinitis pigmentosa (an inherited condition of the eye);

• blindness in one or both eyes;

• bleeding problems;

• a stomach ulcer;

• pulmonary veno-occlusive disease (PVOD);

• liver or kidney disease;

• a blood cell disorder such as sickle cell anemia, multiple myeloma, or leukemia;

• a physical deformity of the penis (such as Peyronie's disease); or

• if you have been told you should not have sexual intercourse for health reasons.

Sildenafil can decrease blood flow to the optic nerve of the eye, causing sudden vision loss. This has occurred in a small number of people taking sildenafil, most of whom also had heart disease, diabetes, high blood pressure, high cholesterol, or certain pre-existing eye problems, and in those who smoked or were over 50 years old. It is not clear whether this medicine is the actual cause of vision loss.

Tell your doctor if you are pregnant. It is not known whether sildenafil will harm an unborn baby. However, having pulmonary arterial hypertension (PAH) during pregnancy may cause complications such as heart failure, stroke, or medical problems in both mother and baby. The benefit of treating PAH with Revatio may outweigh any risks to the baby.

It may not be safe to breast-feed while using this medicine. Ask your doctor about any risk.

Do not give this medication to anyone under 18 years old without medical advice.

Since Viagra is used as needed, you are not likely to miss a dose.

If you miss a dose, take the medicine as soon as you can, but skip the missed dose if it is almost time for your next dose. Do not take two doses at one time.

Seek emergency medical attention or call the Poison Help line at 1-800-222-1222.

Drinking alcohol with Revatio can cause side effects.

Grapefruit may interact with sildenafil and lead to unwanted side effects. Avoid the use of grapefruit products.

Avoid using any other medicines to treat impotence, such as alprostadil or yohimbine, without first talking to your doctor.

Get emergency medical help if you have signs of an allergic reaction to Revatio: hives; difficulty breathing; swelling of your face, lips, tongue, or throat.

Stop taking Revatio and get emergency medical help if you have:

• heart attack symptoms - chest pain or pressure, pain spreading to your jaw or shoulder, nausea, sweating;

• vision changes or sudden vision loss; or

• erection is painful or lasts longer than 4 hours (prolonged erection can damage the penis).

Call your doctor at once if you have:

• severe shortness of breath, cough with foamy mucus;

• ringing in your ears, or sudden hearing loss;

• irregular heartbeat;

• swelling in your hands, ankles, or feet;

• a seizure; or (convulsions); or

• a light-headed feeling, like you might pass out.

Common Revatio side effects may include:

• flushing (warmth, redness, or tingly feeling);

• headache, dizziness;

• abnormal vision (blurred vision, changes in color vision)

• runny or stuffy nose, nosebleeds;

• sleep problems (insomnia);

• muscle pain, back pain; or

• upset stomach.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

Do not take Revatio with similar medications such as avanafil (Stendra), tadalafil (Cialis) or vardenafil (Levitra). Tell your doctor about all other medications you use.

Tell your doctor about all your other medicines, especially:

• drugs to treat high blood pressure or a prostate disorder;

• antifungal medicine - ketoconazole or itraconazole; or

• medicine to treat HIV/AIDS - ritonavir and others.

This list is not complete. Other drugs may interact with sildenafil, including prescription and over-the-counter medicines, vitamins, and herbal products. Not all possible drug interactions are listed here.