Society, ever since its evolution has always regarded sex as a natural act, similar to eating and drinking. Hinduism and Judaism even consider it to be a holy act when performed within the bonds of marriage. The Torah states, "It is not good for men to be alone." (Gen: 2:18) .Sexual intercourse within marriage is a right and was never a taboo on religious grounds, nor has any government ever interfered in this activity.

Sexual intercourse, as a means for procreation is inherently essential to the continuation of species of any particular generic line. Sexual intercourse is not only a form of pleasure ,but at a higher emotional level sexual intercourse is often ,though not always seen as the ultimate physical expression of feelings of romantic love between two humans.

It is essential therefore for sexual intercourse to be an enjoyable experience .But the reality however is not always so. And on most occasions it is because of the male partner's inability to have a proper erection for effective penetration. In fact more than half of all men over 40 have difficulties getting or maintaining an erection. This problem also called Erectile Dysfunction (E. D.) occurs when there is a lack of blood flow to the penis. This means that a man can have trouble getting and keeping an erection long enough to have sex. It can happen regularly or once in a while.

However the strong urge among humans to conquer all things desirable, E.D to is no obstacle to an enjoyable sexual experience. The breakthrough in the cure of E.D came in the year 1994, when pharmaceutical giant Pfizer announced the launching of Viagra, as the ultimate medicine for the cure of E.D .Viagra has been hailed as the greatest gift of medical science in the last century.

Viagra hit the market in 1998 and became popular overnight. Cialis and Levitra followed next and according to many is an improvement on Viagra.

Although pills have made life for victims of erectile dysfunction easy its usage is not without side effects. The most common side effects are headache, upset stomach, delayed backache or muscle ache. Although rare, men who experience an erection for more than 4 hours should seek immediate medical attention.