The body produces testosterone naturally, but natural testosterone cannot be used as a medicine. In the normal body, testosterone is released continuously into the bloodstream by the pituitary gland. In males, it is also released by the testes. It reaches different parts of the body, has its effects, and then body enzymes quickly break it down.

It was in the late 1930s when the substances, popularly known as anabolic steroids were first developed for the treatment of hypogonadism, which is incompetence of the gonads, especially due to low production of testosterone in males. Hypogonadism is the condition in which male testes do not produce sufficient testosterone for normal growth, development, and sexual functioning. It results in deficient development of secondary sex characteristics and in prepubertal males, a body with long legs and a short trunk.