Viagra

What is Viagra?

Viagra (sildenafil) relaxes muscles and increases blood flow to particular areas of the body.

Sildenafil under the name Viagra is used to treat erectile dysfunction (impotence) in men. Another brand of sildenafil is Revatio, which is used to treat pulmonary arterial hypertension and improve exercise capacity in men and women. Do not take Viagra while also taking Revatio, unless your doctor tells you to.

Viagra may also be used for other purposes not listed in this medication guide.

Important information about Viagra

Do not take Viagra if you are also using a nitrate drug for chest pain or heart problems. This includes nitroglycerin (Nitrostat, Nitrolingual, Nitro-Dur, Nitro-Bid, and others), isosorbide dinitrate (Dilatrate-SR, Isordil, Sorbitrate), and isosorbide mononitrate (Imdur, ISMO, Monoket). Nitrates are also found in some recreational drugs such as amyl nitrate or nitrite ("poppers"). Taking Viagra with a nitrate medicine can cause a sudden and serious decrease in blood pressure. 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 Viagra.

Do not take Viagra more than once a day. Allow 24 hours to pass between doses. Contact your doctor or seek emergency medical attention if your erection is painful or lasts longer than 4 hours. A prolonged erection (priapism) can damage the penis.

Viagra 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 Viagra, most of whom also had heart disease, diabetes, high blood pressure, high cholesterol, or certain pre-existing eye problems, and in those who smoke or are over 50 years old. It is not clear whether Viagra is the actual cause of vision loss.

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

Before taking Viagra

Do not take Viagra if you are also using a nitrate drug for chest pain or heart problems. This includes nitroglycerin (Nitrostat, Nitrolingual, Nitro-Dur, Nitro-Bid, and others), isosorbide dinitrate (Dilatrate-SR, Isordil, Sorbitrate), and isosorbide mononitrate (Imdur, ISMO, Monoket). Nitrates are also found in some recreational drugs such as amyl nitrate or nitrite ("poppers"). Taking Viagra with a nitrate medicine can cause a sudden and serious decrease in blood pressure.

To make sure you can safely take Viagra, tell your doctor if you have any of these other conditions:

heart disease or heart rhythm problems;
a recent history (in the past 6 months) of a heart attack, stroke, or congestive heart failure;
high or low blood pressure;
coronary artery disease;
liver or kidney diseas;
a blood cell disorder such as sickle cell anemia, multiple myeloma, or leukemia;
a bleeding disorder such as hemophilia;
a stomach ulcer;
retinitis pigmentosa (an inherited condition of the eye);
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.
Viagra 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 Viagra, most of whom also had heart disease, diabetes, high blood pressure, high cholesterol, or certain pre-existing eye problems, and in those who smoke or are over 50 years old. It is not clear whether Viagra is the actual cause of vision loss. Stop using Viagra and get emergency medical help if you have sudden vision loss.

FDA pregnancy category B: This medication is not expected to be harmful to an unborn baby. Do not use Viagra without telling your doctor if you are pregnant or plan to become pregnant during treatment. It is not known if sildenafil passes into breast milk or if it could harm a nursing baby. Do not use this medication without telling your doctor if you are breast-feeding a baby.

How should I take Viagra?

Take Viagra exactly as prescribed by your doctor. Do not take in larger or smaller amounts or for longer than recommended. Follow the directions on your prescription label.

Viagra is usually taken only when needed, 30 minutes to 1 hour before sexual activity. You may take it up to 4 hours before sexual activity. Do not take Viagra more than once per day.

Viagra can help you have an erection when sexual stimulation occurs. An erection will not occur just by taking a pill. Follow your doctor's instructions.

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 Viagra.

Store this medication at room temperature away from moisture and heat.

What happens if I miss a dose?

Viagra is used as needed, so you are not likely to be on a dosing schedule.

What happens if I overdose?

Seek emergency medical attention or call the Poison Help line at 1-800-222-1222. Overdose symptoms may include chest pain, nausea, irregular heartbeat, and feeling light-headed or fainting.

What should I avoid while taking Viagra?

Avoid drinking alcohol, which can increase some of the side effects of Viagra. Avoid using other medicines to treat impotence, such as alprostadil (Caverject, Muse, Edex) or yohimbine (Yocon, Yodoxin, others), without first talking to your doctor.

Viagra side effects

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

Stop using Viagra and call your doctor at once if you have a serious side effect such as:

sudden vision loss;
ringing in your ears, or sudden hearing loss;
chest pain or heavy feeling, pain spreading to the arm or shoulder, nausea, sweating, general ill feeling;
irregular heartbeat;
swelling in your hands, ankles, or feet;
shortness of breath;
vision changes;
feeling light-headed, fainting; or
penis erection that is painful or lasts 4 hours or longer.
Less serious Viagra side effects may include:

warmth or redness in your face, neck, or chest;
stuffy nose;
headache;
memory problems;
upset stomach; or
back pain.
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.

What other drugs will affect Viagra?

Do not take Viagra with similar medications such as tadalafil (Cialis) or vardenafil (Levitra).

Do not take Viagra if you are also using a nitrate drug for chest pain or heart problems, including nitroglycerin (Nitrostat, Nitrolingual, Nitro-Dur, Nitro-Bid, Minitran, Deponit, Transderm-Nitro), isosorbide dinitrate (Dilatrate-SR, Isordil, Sorbitrate), and isosorbide mononitrate (Imdur, ISMO, Monoket), or recreational drugs such as amyl nitrate or nitrite ("poppers").

Before taking Viagra, tell your doctor about all other medications you use for erectile dysfunction, or if you are using any of the following medications:

bosentan (Tracleer);
cimetidine (Tagamet, Tagamet HB);
conivaptan (Vaprisol);
imatinib (Gleevec);
isoniazid (for treating tuberculosis);
rifampin (Rifadin, Rimactane, Rifater, Rifamate);
an antidepressant such as nefazodone;
an antibiotic such as clarithromycin (Biaxin), dalfopristin/quinupristin (Synercid), erythromycin (E.E.S., EryPed, Ery-Tab, Erythrocin, Pediazole) or telithromycin (Ketek);
antifungal medication such as itraconazole (Sporanox), ketoconazole (Nizoral), miconazole (Oravig), or voriconazole (Vfend);
heart or blood pressure medication such as diltiazem (Cardizem, Dilacor, Tiazac), doxazosin (Cardura), nicardipine (Cardene), quinidine (Quin-G), or verapamil (Calan, Covera, Isoptin, Verelan); or
HIV/AIDS medicine such as atazanavir (Reyataz), delavirdine (Rescriptor), fosamprenavir (Lexiva), indinavir (Crixivan), nelfinavir (Viracept), saquinavir (Invirase), or ritonavir (Norvir, Kaletra).
This list is not complete and there may be other drugs that can interact with Viagra. Tell your doctor about all the prescription and over-the-counter medications you use. This includes vitamins, minerals, herbal products, and drugs prescribed by other doctors. Do not start using a new medication without telling your doctor.