What is Viagra and when do we use?

Viagra is the first representative of a new group of drugs called phosphodiesterase type 5. It works by promoting relaxation of blood vessels in the penis during sexual arousal. Blood flows more easily into the penis, which allows to obtain an erection in a natural way. If you do not suffer from erectile dysfunction, it should not take Viagra. Similarly, if you are a woman, do not take it. Viagra is indicated on prescription for the treatment of erectile dysfunction, sometimes referred to as impotence. This is the case when a man can not get or maintain an erection of the penis rigid sufficient for sexual intercourse. Viagra does not increase libido and does not affect fertility.