Brand Viagra (Sildenafil)

A small number of patients have lost eyesight in one eye after taking Viagra. This type of vision loss is known by the name of anterior ischemic optic neuropathy non-arteritic (NAION, by its initials in English). NAION causes a sudden loss of eyesight after blockage of blood flow to the optic nerve. It is not known at this time if tadalafil causes NAION. NAION also happens in patients who do not take this medicine. People with an increased risk of NAION include those who: Have heart disease. Are older than 50 years of age. Suffer from diabetes. Have high blood pressure. Have high cholesterol. Smoke. Have an eye problem. Stop using Viagra if you have any loss in your eyesight and seek medical attention immediately. Do not take Viagra if you are using a nitrate drug for chest pain or heart problems. This includes nitroglycerin (Nitrostat, Nitrolingual, Nitro-Dur, Nitro-Bid, Minitran, Deponit, Transderm-Nitro, others), isosorbide dinitrate (Dilitrate-SR, Isordil, Sorbitrate) and isosorbide mononitrate (Imdur, ISMO, Monoket) . Nitrates are also found in recreational drugs such as amyl nitrate or nitrite ("poppers"). Contact your doctor or seek emergency medical attention for any erection that lasts more than 4 hours. A sustained erection can damage the penis. Refrain from further sexual activity and notify your doctor if you experience headache, dizziness, nausea, or angina (pain, tightness, discomfort, numbness, or tingling in the chest, arms, neck, or jaw) during sexual intercourse . Viagra should not take more than once a day.