Sildenafil

Brand Name: Viagra

Prescription Needed: Yes

What is this drug used for?

Sildenafil is used to produce erections in some men who are having problems with achieving or maintaining an erection after being sexually stimulated. It is not used to increase your sex drive and will not work if you are not sexually aroused.

Is there any reason not to take this drug?

You should not take this drug if you are allergic to sildenafil or if you are taking any medication that contains nitroglycerin. Tell your doctor if you have or have ever had:

  • a heart attack stroke or heart rhythm problem
  • chest pain (angina)
  • problems with your kidney or liver
  • high or low blood pressure
  • a condition called priapism
  • any blood problems like sickle cell anemia multiple myeloma or leukemia - this may increase your chances for a side effect called priapism
  • deformed penis including curved penis or birth defects of the penis
  • an eye condition called retinitis pigmentosa
  • problems with heartburn or a condition called esophagitis
  • problems with hemorrhoids

What about possible side effects?

The most common side effects to sildenafil are:

  • headache
  • flushing (feeling of warmth)
  • upset stomach or heartburn
  • stuffy nose
  • diarrhea

These side effects tend to be related to dose and should go away with time especially as the drug is usually out of your body after approximately 24 hours (although it could take longer depending on your age other medical conditions and other medications you may be taking).

Less common and possibly severe side effects include:

  • rash
  • bleeding hemorrhoids (some cases reported)
  • feeling dizzy or lightheaded
  • painful or prolonged erection (longer than four hours) - rare
  • seizures (rare case reports)
  • changes in vision
  • low blood pressure
  • chest pain heart rhythm problems heart attack mini-strokes - cases have been reported

This is not a complete list of side effects. If you are concerned about these or other unusual symptoms while taking this medication ask your doctor and/or pharmacist for more information and advice.

What if I am taking other drugs?

Always provide your doctor with a list of all other drugs you are taking (including over-the-counter medications and herbal/natural products) as they may interact and may change the safety or effectiveness of either drug. Tell your doctor specifically if you are taking any of these drugs as these are the most common interactions and he/she may need to make changes or monitor you more closely:

  • medications for high blood pressure (especially doxazosin terazosin prazosin) - may increase your chances of having low blood pressure
  • itraconazole ketoconazole fluconazole cimetidine HIV protease inhibitors (e.g. ritonavir) amiodarone clarithromycin erythromycin diltiazem verapamil - may increase the amount of sildenafil in your blood
  • Isosorbide dinitrate or nitroglycerin - AVOID this combination with sildenafil as it can cause significant low blood pressure and possibly severe heart side effects
  • phenobarbital rifampin phenytoin - may decrease the amount of sildenafil in your blood

This is not a complete list of drug interactions. Ask your doctor or pharmacist to review your list of medications.

Other information

How to take: You should take this medication approximately one hour before planned sexual activity. Although it varies it may take between 30 minutes and one hour to take effect (longer if you take the medication with a high-fat meal). You must be sexually aroused in order for this drug to work. If you find that the drug is not working talk to your doctor as he/she may be able to make a change in dose.

Do not take more than one dose of this medication per day.

Children: Not prescribed to those under the age of 18.

Seniors: Lower doses (usually 25mg) are necessary especially at the start of therapy.

Pregnant women: Not recommended.

Women who are nursing. Not recommended.

People who drive or operate machinery: Should not do so until they know the impact this drug has on them personally. This drug can cause dizziness and vision problems in some people.

Overdose: If you experience any unusual reactions or if you seriously exceed the recommended dosage call your doctor or 911.

Stopping the drug: You can stop taking this drug when you no longer need it.

If you miss a dose: Take the next dose as required but never take more than one dose daily.

Storage conditions: Closed container; cool dry location away from excess moisture (not in the bathroom); always out of reach of children.

Dietary precautions: It may take longer for the medication to start working if you take it with a high fat meal.