The frequency of patients reporting improvement of erections in response to a global question in four of the randomized, double-blind, parallel, placebo-controlled fixed dose studies patients of 12 to 24 weeks duration is shown in Figure 7. In some patients, the use of VIAGRA with alpha-blockers can lead to a drop in blood pressure or to fainting medicines called HIV protease inhibitors, such as ritonavir Norvir , indinavir sulfate Crixivan , saquinavir Fortovase or Invirase , or atazanavir sulfate Reyataz some types of oral antifungal medicines, such as ketoconazole Nizoral and itraconazole Sporanox some types of antibiotics, such as clarithromycin Biaxin , telithromycin Ketek , or erythromycin other medicines that treat high blood pressure other medicines or treatments for ED VIAGRA contains sildenafil, which is the same medicine found in another drug called REVATIO. Some people may also have ringing in their ears tinnitus or dizziness. It is eliminated predominantly by hepatic metabolism mainly CYP3A4 and is converted to an active metabolite with properties similar to the parent, sildenafil. You need a prescription from a doctor to obtain sildenafil. Your doctor will discuss the best treatment plan for you. In these studies, involving about patients, analyses of patient diaries showed no effect of VIAGRA on rates of attempted intercourse about 2 per week , but there was clear treatment-related improvement in sexual function: per patient weekly success rates averaged 1.Shop Walgreens your way. Pickup in as little as 30 minutes. FREE Same Day Delivery. FREE Shipping. myWalgreens® Credit Card. We’re here to help keep you protected. Schedule vaccines. Get tested for flu & COVID Shop wellness essentials.  · Dosage Forms and Strengths. VIAGRA is supplied as blue, film-coated, rounded-diamond-shaped tablets containing sildenafil citrate equivalent to 25 mg, 50 mg, or mg of sildenafil. Tablets are debossed with PFIZER on one side and VGR25, VGR50 or VGR on the other to indicate the dosage strengths. 4. The History of Supplementation for Sexual Health. Many of the herbs contained in sexual wellness supplements have been used for centuries to address problems. These problems include reduced libido (sex drive) and erectile dysfunction (trouble getting or maintaining an erection). Ancient cultures believed that certain plants and foods functioned.