Shake the liquid well for 10 seconds before each use to mix the medication evenly. Sildenafil treats erectile dysfunction by increasing blood flow to the penis during sexual stimulation. If you are taking sildenafil to treat erectile dysfunction, you should know that it does not cure erectile dysfunction or increase sexual desire. Most erectile dysfunction medications belong to the drug class known as PDE5 inhibitors , which help relax the muscles and increase blood flow to allow for a full erection. The products discussed in this site may have different product labeling in different countries.Sildenafil, sold under the brand name Viagra, among others, is a medication used to treat erectile dysfunction and pulmonary arterial hypertension. [4] [8] It is also sometimes used off-label for the treatment of certain symptoms in secondary Raynaud’s phenomenon. [9] It is unclear if it is effective for treating sexual dysfunction in females. [8]. So it’s unknown whether a mg dose is more likely to cause more side effects than a mg dose. If you’re concerned about the risk for side effects with higher doses of Viagra, talk with. Sildenafil Citrate Coupons, Prices, and Savings Card. Brand Names: Revatio, Viagra. Sildenafil is used to treat male sexual function problems (impotence or erectile dysfunction-ED). Learn more about sildenafil oral. 1. Sildenafil is used to treat high blood pressure in the lungs (pulmonary hypertension).