About Viagra


What is Viagra?

Erectile dysfunction, or ED, is the medical term for impotence - the inability to get and/or keep an erection sufficient for satisfactory sexual activity. About 30 million men in the United States suffer from some degree of ED, including about half of all men aged 40 to 70 years.

VIAGRA® enables many men with ED to respond to sexual stimulation. When a man is sexually aroused, the arteries in the penis relax and widen, allowing more blood to flow into the penis. As the arteries in the penis expand and harden, the veins that normally carry blood away from the penis become compressed, restricting the blood flow out of the penis. With more blood flowing in and less flowing out, the penis enlarges, resulting in an erection.

If the nerves or blood vessels associated with this process aren't working properly, a man may not be able to get an erection. VIAGRA® increases blood flow to the penis, so that when a man is sexually aroused, he can get and keep an erection. When the sexual encounter is over, the erection goes away.
VIAGRA® improves erections in up to 4 of 5 men who take it, regardless of how long they have had ED, what caused it, or how old they are.

VIAGRA® comes in different doses (25 mg, 50 mg, and 100 mg). Like many medications, your health care provider may have to adjust your initial VIAGRA® dose if it doesn't produce the desired results or you're bothered by side effects. Do not take more VIAGRA® than your health care provider prescribes, and do not take VIAGRA® more than once a day.

If you are older than 65 years, have a serious liver or kidney problem, or are taking protease inhibitors, such as for the treatment of HIV, your health care provider may start you at the lowest (25 mg) dose of VIAGRA®.


For most patients, VIAGRA® should not be taken more than once a day. In patients taking certain protease inhibitors (such as for the treatment of HIV), it is recommended to not exceed a maximum single dose of 25 mg of VIAGRA® in a 48-hour period.