Drug interactions may change how your medications work or increase your risk for serious side effects. This document does not contain all possible drug interactions. Keep a list of all the products you use (including prescription/nonprescription drugs and herbal products) and share it with your doctor and pharmacist. Do not start, stop, or change the dosage of any medicines without your doctor's approval.

Some products that may interact with this drug include: certain recreational drugs ("poppers") containing amyl/butyl nitrite, alpha blocker medication (such as doxazosin, prazosin, terazosin), bosentan.

Other medications can affect the removal of sildenafil from your body, which may affect how sildenafil works. Examples include cimetidine, anticonvulsants (such as carbamazepine, phenobarbital, phenytoin), azole antifungals (such as ketoconazole, itraconazole), macrolide antibiotics (such as erythromycin), rifamycins (such as rifabutin), HIV drugs (such as ritonavir, saquinavir, delavirdine), St. John's wort, among others.

Sildenafil may interact with certain chest pain medications (nitrates such as nitroglycerin, isosorbide) causing a dangerous drop in blood pressure. Do not take sildenafil if you also use nitrates. Talk with your doctor or pharmacist for more details and for information on what to do if you get unusual chest pain.

Do not take this medication with any other product that contains sildenafil or other similar medications for erection problems/pulmonary hypertension (such as tadalafil, vardenafil).

OVERDOSE: If overdose is suspected, contact a poison control center or emergency room immediately. US residents can call the US National Poison Hotline at 1-800-222-1222. Canada residents can call a provincial poison control center. Symptoms of overdose may include severe dizziness, fainting, painful/prolonged erection.

NOTES: Do not share this medication with others.

Medical tests (such as blood pressure, eye exams) may be performed periodically to monitor your progress or check for side effects.

MISSED DOSE: Not applicable.

STORAGE: Store at room temperature away from light and moisture. Do not store in the bathroom. Keep all medications away from children and pets.

Do not flush medications down the toilet or pour them into a drain unless instructed to do so. Properly discard this product when it is expired or no longer needed. Consult your pharmacist or local waste disposal company for more details about how to safely discard your product.

Information last revised December 2010. Copyright(c) 2010 First Databank, Inc.