Viagra
® (
sildenafil citrate) is a prescription medication used for treating problems with obtaining or maintaining an erection.
Viagra is manufactured by Pfizer.
Viagra has been licensed for the treatment of
erectile dysfunction. Erectile dysfunction (
ED), also known as
impotence, can be a total inability to achieve erection, an inconsistent ability to do so, or a tendency to sustain only brief erections. Essentially, erectile dysfunction is the repeated inability to get or keep an erection firm enough for sexual intercourse.
Viagra works by blocking a chemical that causes blood to flow out of the penis. More blood in the penis means an improved erection.
In previous clinical studies, up to 88 percent of men reported that Viagra improved their erections. Viagra was also shown to be effective in men with certain medical conditions and following various types of surgeries
(see Effects of Viagra for more information).
When Does Viagra Start Working?
Many men wonder, "How long do I have to wait for Viagra to work?" The waiting time varies depending on the individual. In clinical studies, Viagra began to work in as little as 14 minutes. For most people, though, it begins working within 30 minutes. Viagra can continue to work for at least four hours; but, on average, the response decreases after about two hours.
When and How Do I Take Viagra?
Here are some general considerations regarding when and how to take Viagra:
- Viagra comes in tablet form. It is taken as needed, usually one hour before sexual activity. However, it is not recommended that you take Viagra more than once a day.
- It is recommended that you take your Viagra dose with a glass of water, though you may take it with or without food. If you take your Viagra dose with food, keep in mind that fatty meals may decrease the levels of Viagra in the blood.
- Do not break, chew, or crush the Viagra tablets.
- For Viagra to work properly, you have to take it as prescribed. Viagra will not work if you stop taking it.
The dose of Viagra your healthcare provider recommends will vary depending on a number of factors, including:
- Your age
- Other medical conditions you may have
- Other medications you may be currently taking.
As always, do not adjust your dose unless your healthcare provider specifically instructs you to do so.
(Click Viagra Dosage for more information about dosing for Viagra.)
(The Viagra side effects listed below are NOT a complete list of possible side effects of Viagra. Your healthcare provider can discuss a more complete list of Viagra side effects with you.)
As with any medicine, there are possible side effects with Viagra; however, not everyone who takes Viagra will experience side effects. In fact, most people tolerate Viagra well. When people do develop side effects, in most cases they are minor, meaning they require no treatment or are easily treated by you or your healthcare provider.
The most common side effects of Viagra include:
- Headache --16 percent of people
- Facial flushing -- 10 percent of people
- Indigestion, known as dyspepsia -- 7 percent of people
- Nasal congestion -- 4 percent of people
- Urinary tract Infections (UTI) -- 3 percent of people
- Vision problems, including trouble telling the difference between blue and green, increased sensitivity to light, or blurred vision -- 3 percent of people
- Diarrhea -- 3 percent of people
- Dizziness -- 2 percent of people
- Unexplained rash -- 2 percent of people.
In people taking Viagra or other PDE5 inhibitors, there have been rare cases of a condition called non-arteritic anterior ischemic optic neuropathy (NAION). This condition can lead to sudden loss of vision in one or both eyes. If you experience any loss of vision while on Viagra, contact your healthcare provider immediately
(see Viagra and Blindness).
Drug Interactions With Viagra
There are a number of medicines that Viagra can potentially interact with.
Viagra: What Should I Tell My Healthcare Provider?
Prior to taking Viagra, you should tell your healthcare provider if you have:
Also, tell your healthcare provider about all the medicines you take, including prescription and non-prescription medicines,
antacids, vitamins, and herbal supplements.
Who Should Not Take Viagra?
You should not take Viagra if:
- You are allergic to Viagra or any component of sildenafil citrate. Your healthcare provider or pharmacist has a list of the inactive ingredients.
- You are taking a nitrate for angina.
Only a small number of people have overdosed on Viagra. Therefore, Viagra overdose symptoms are not well-known. If you happen to overdose on Viagra, seek medical attention immediately.
Viagra should be stored at room temperature.
Keep Viagra and all medications out of the reach of children.
There are several strengths of Viagra tablets available. These include:
- Viagra 25 mg
- Viagra 50 mg
- Viagra 100 mg.
Currently, there is no generic Viagra available for sale.