Tell your doctor and pharmacist if you are allergic to sildenafil or any other drugs.
Tell your doctor and pharmacist what prescription and nonprescription medications you are taking, especially amlodipine Norvasc or other medications for high blood pressure, cimetidine Tagamet, Tagamet HB, erythromycin, HIV protease inhibitors such as ritonavir Norvir and saquinavir Invirase, isosorbide Imdur, Ismo, Isordil, and others, itraconazole Sporanox, ketoconazole Nizoral, nitroglycerin Nitro-Bid, Nitrostat, and others, other medications to treat impotence, phenobarbital, rifampin Rifadin, Rimactane,and vitamins.
tell your doctor if you have or have ever had a bleeding disorder heart, kidney, or liver disease a heart attack irregular heartbeats angina a stroke high or low blood pressure sickle cell anemia multiple myeloma leukemia conditions affecting the shape of the penis e.g., angulation, cavernosal fibrosa, or Peyronies disease or a condition known as retinitis pigmentosa.
if you are having surgery, including dental surgery, tell your doctor or dentist that you take sildenafil.
tell your doctor if you use amyl nitrate, amyl nitrite, or butyl nitrate.