Viagra Oral

Viagra Oral Interactions

Your doctor or pharmacist may already be aware of any possible drug interactions and may be monitoring you for them. Do not start, stop, or change the dosage of any medicine before checking with them first.

See also How To Use section for drug-food interactions.

This drug should not be used with the following medications because very serious (possibly fatal) interactions may occur:

• nitrates (e.g., nitroglycerin, isosorbide)
• nitroprusside (or any "nitric oxide donor" drugs)
• recreational drugs called "poppers" containing amyl or butyl nitrite

If you are currently using any of these medications, tell your doctor or pharmacist before starting sildenafil.

Before using this medication, tell your doctor or pharmacist of all prescription and nonprescription/herbal products you may use, especially of:

• alpha-blocker medication (e.g., doxazosin, prazosin, terazosin)
• other medications for impotence
• bosentan
• high blood pressure medicines
• drugs affecting liver enzymes that remove sildenafil from your body (such as azole antifungals including ketoconazole/itraconazole, macrolide antibiotics including erythromycin, cimetidine, delavirdine, rifamycins including rifabutin/rifampin, St. John's wort, certain anti-seizure medicines including carbamazepine)

If you are taking an HIV protease inhibitor (e.g., ritonavir, saquinavir), do not take more than a 25 milligrams dose of sildenafil in a 48 hour period.

If you are taking more than a 25 milligrams dose of sildenafil and are also taking an alpha-blocker medication (e.g., doxazosin, prazosin, terazosin) for various conditions (e.g., enlarged prostate), separate the time between taking these medications by more than 4 hours.

This document does not contain all possible interactions. Therefore, before using this product, tell your doctor or pharmacist of all the products you use. Keep a list of all your medications with you, and share the list with your doctor and pharmacist.