Sildenafil is a medication that is taken before sexual activity and allows men with erectile dysfunction (ED) to achieve and maintain an erection. ED or impotence happens when a man is unable to achieve or maintain an erection long enough for sexual intercourse.

ED can be caused by medical conditions like high blood pressure, diabetes, prostate problems, and heart disease. It can also be a side effect of the medications taken for these conditions. Personal lifestyle factors such as stress, alcohol, and/or tobacco use can also play a role.

During surgery or radiation to the pelvic area (including prostate, bladder, and rectal procedures), there can be damage to the nerves that supply the penis. This can lead to either temporary or permanent impotence. Some surgeons perform "nerve-sparing" surgeries to try to preserve erectile function. Even in these cases, however, the nerves will suffer some injury, and it can take 18-24 months or longer for erectile function to return. These men should be treated aggressively with oral or injectable medications for ED in order to speed the recovery of the nerves and to prevent muscle wasting in the penis.

How to Take Sildenafil

Sildenafil is taken by mouth up to once a day. It should be taken around 60 minutes before sex but can be taken as much as four hours or as few as 30 minutes before sex. It works for up to 4 hours. It can be taken with or without food.
Your provider will find the dose that is best for you. Some men need dose changes to find the dose that works best for them.
Men who take sildenafil will not have an erection without sexual stimulation. This drug is not an aphrodisiac and does not affect libido or desire. Having multiple intercourse sessions with one dose has not been studied.
You should not adjust your dose without talking to your provider first.
Men who take nitrates, such as nitroglycerin, Nitro-Bid, Isordil, or Deponit should not take sildenafil.
Men who take Cardura, Flomax, or Hytrin for urinary symptoms should not take sildenafil.
This medication can affect how other medications work. Be sure your provider and pharmacist know all the medications (prescription and over-the-counter) and supplements you take.

Storage and Handling

Store your medication in the original, labeled container at room temperature and in a dry location (unless otherwise directed by your healthcare provider or pharmacist). This medication should not be stored in a pillbox since it should only be taken prior to sexual activity. Keep containers out of reach of children and pets. Ask your care team where to return any unused medication for disposal. Do not flush down the toilet or throw it in the trash.

Where do I get this medication?

Sildenafil is available through most pharmacies.

Insurance Information

This medication may be covered under your prescription drug plan. Patient assistance may be available to qualifying individuals without prescription drug coverage through the pharmaceutical company that makes the medication. Your care team can help you find these resources if they are available.

Possible Side Effects of Sildenafil

There are a few side effects you may have while taking sildenafil. Talk to your providers if you have concerns about these side effects. Do not take a higher dose of sildenafil than your provider orders for you.

Headache, facial flushing, stuffy or runny nose, and upset stomach can occur.
Less frequent side effects include blurry vision, a bluish hue to the field of vision, difficulty telling the difference between the colors blue and green, sensitivity to light, or a sudden loss of vision or hearing.

If you experience any of the following while using sildenafil, you should seek immediate medical attention:

An erection lasting more than 4 hours.
Chest, arm or neck pain, or nausea during sexual activity.
Sudden loss of vision in one or both eyes, loss of hearing, ringing in the ears, or dizziness.

Reproductive Concerns

Remember, sildenafil does not protect against sexually transmitted diseases, nor does it prevent pregnancy. Effective birth control is recommended during cancer treatment. Even if you are not producing sperm, you could still be fertile and conceive.