Viagra is an anti-impotence drug manufactured by Pfizer with an active ingredient sildenafile citrate for treatment of male impotence. Sildenafile citrate relaxes the muscles and increases the blood flow to particular areas of the body. The intake of Viagra increases the ability to achieve and sustain erection on being sexually stimulated. Men taking Viagra have reported an amplified sex drive, increased stamina, and quicker recharge. Viagra works together with sexual stimulation to help achieve maximum sexual satisfaction. However, Viagra does not guarantee protection from getting sexually transmitted diseases, including HIV and Hepatitis.