- If you become dizzy or nauseated, or have pain, numbness, or tingling in your chest, arms, neck, or jaw during sexual activity, stop and call your doctor right away. You could be having a serious side effect of sildenafil.
- Stop using sildenafil and get emergency medical help if you have sudden vision loss.
- Get emergency medical help if you have any of these signs of an allergic reaction: hives; difficulty breathing; swelling of your face, lips, tongue, or throat.
- Stop using sildenafil and call your doctor at once if you have any of these serious side effects:
- chest pain or heavy feeling, pain spreading to the arm or shoulder, nausea, sweating, general ill feeling;
- irregular heartbeat;
- swelling in your hands, ankles, or feet;
- shortness of breath;
- vision changes;
- feeling light-headed, fainting; or
- penis erection that is painful or lasts 4 hours or longer.
- Continue taking sildenafil and talk with your doctor if you have any of these less serious side effects:
- warmth or redness in your face, neck, or chest;
- stuffy nose;
- headache;
- upset stomach; or
- back pain.
- side effects other than those listed here may also occur. Talk to your doctor about any side effect that seems unusual or that is especially bothersome.
What other drugs will affect sildenafil?
- Do not take sildenafil if you are also using a nitrate drug for chest pain or heart problems, including nitroglycerin (Nitrostat, Nitrolingual, Nitro-Dur, Nitro-Bid, Minitran, Deponit, Transderm-Nitro), isosorbide dinitrate (Dilatrate-SR, Isordil, Sorbitrate), and isosorbide mononitrate (Imdur, ISMO, Monoket), or recreational drugs such as amyl nitrate or nitrite (“poppers”).
- Before taking sildenafil, tell your doctor if you are using any of the following medications:
- bosentan (Tracleer);
- cimetidine (Tagamet, Tagamet HB);
- an antibiotic such as erythromycin (E-Mycin, Eryc, Ery-Tab) or clarithromycin (Biaxin);
- doxazosin (Cardura), prazosin (Minipress), Terazosin (Hytrin);
- HIV medicines such as amprenavir (Agenerase), tipranavir (Aptivus), darunavir (Prezista), efavirenz (Sustiva), nevirapine (Viramune), indinavir (Crixivan), saquinavir (Invirase, Fortovase), lopinavir/ ritonavir (Kaletra), fosamprenavir (Lexiva), ritonavir (Norvir), atazanavir (Reyataz), or nelfinavir (Viracept);
- an antifungal medication such as itraconazole (Sporanox) or ketoconazole (Nizoral);
- carbamazepine (Tegretol), phenobarbital (Luminal), or phenytoin (Dilantin); or
- rifampin (Rifadin, Rimactane) or rifabutin (Mycobutin).
- If you are using any of these drugs, you may not be able to take sildenafil, or you may need dosage adjustments or special tests during treatment.
- There may be other drugs not listed that can affect sildenafil. Tell your doctor about all the prescription and over-the-counter medications you use. This includes vitamins, minerals, herbal products, and drugs prescribed by other doctors. Do not start using a new medication without telling your doctor.
