How Viagra works?
Viagra works by relaxing arteries in the penis and thus allowing more blood into penile tissues when a man is sexually stimulated; at the same time the veins through which blood flows away from penis are compressed and allow less blood to flow out of the penis. This causes strong and long lasting erection. When the sexual intercourse is over, the penis naturally returns to its flaccid condition.
Related questions: How does Viagra work?
