Viagra is the most popular medicine for erectile dysfunction, the inability to keep or get erection for sexual intercourse at all or long enough. There can be many reasons for impotence, such as: age, neurological disorders and psychological problems, wrong life style and vascular causes. More often impotence occurs with the age. Any way, whether it is the result of the psychological or physiological problems or other health conditions, it is not the reason to spell the death on your private and sexual life. Fortunately there are some ways to stay sexually active and lead bright and full-blown style of life. Pills Viagra is one of the most popular prescriptions for treating impotence. It was invented in 1998. Viagra relaxes blood vessels and thus, causes the blood to fill the penis which swells and leads to erection. Positive effects of Viagra are undisputable. Usually men take it in 30 minutes before the sexual intercourse after what the erections can last up to for hours. Healthy people also found positive results from taking Viagra, and many of them use it for making the sexual intercourse amazingly long, but it is not recommended to take it if you don't have such problems. There're also other ways of impotence treatment, but you should always remember, that the best way to prevent the illness, is to avoid its causes.