In the United States alone, as much as 30 million men are affected by Erectile Dysfunction. Viagra (Sildenafil) is very effective drug used for the management of erectile dysfunction in men. Studies have proven that it is the most potent drug for treating ED as much success have been recorded in as much as 80 to 90 percent of men who use the treatment. To treat erectile dysfunction in men, Viagra relaxes muscles found in the walls of the blood vessels and increases blood flow to specific parts of the body. Apart from being used for the treatment of erectile dysfunction, Viagra has not been licensed to use as a treatment for any other purpose. If you can only have penetrative sex for two minutes or less before you ejaculate, then, you are likely suffering from premature ejaculation. Apart from the unnecessary pressure this condition puts on the couple, it can be frustrating in itself.