If you have certain health conditions or are taking certain medications, your doctor may tell you to take sildenafil less often. Sildenafil may cause side effects. Do not stop taking sildenafil without talking to your doctor. Sudden vision loss in one or both eyes can be a sign of a serious eye problem called non-arteritic anterior ischemic optic neuropathy NAION. This can happen if you are sick with fever, diarrhea, or vomiting; sweat a lot; or do not drink enough liquids.Sildenafil (Viagra, Revatio) is a moderately priced drug used to treat erection problems in men. It is also used to treat pulmonary arterial hypertension, a serious heart and lung . Pay as little as $ for Viagra (sildenafil) (Save up to 89% off the average retail price of $) Sign in. Price comparison for Sildenafil 30 tablets 20mg Change Configuration. Kroger Pharmacy estimated retail price. $ Kroger Rx Savings Club price. $ You save 89 % This is your estimated price. · 97% average discount. Depression. 86% average discount. Hypertension. 74% average discount. Urinary Tract Infection. 67% average discount. Based on the average user savings between January and September Search for your prescription on our site or mobile app to see how much you can save. How GoodRx .