Pharmacology The body normally makes sex hormones such as testosterone, which is responsible for normal growth and the development of secondary sexual characteristics. This includes growth of the prostate, testicles, penis, scrotum, body hair, vocal cord thickening, changes in body fat and musculature. When testosterone deficiency occurs, the secondary sexual characteristics and growth of the body is always abnormal. Therefore, one of the indications for testosterone therapy is in the treatment of people who lack testosterone or are infertile. Indications for use Testosterone undecanoate is used to treat conditions in which there is a failure of testosterone secretion such as: Primary failure of the testes to make the hormone Failure of the pituitary to release gonadotropins Bodybuilding Testosterone and its analogues They are widely used by athletes and bodybuilders. The steroid is mainly taken to enhance the body and stimulate the psyche. Most body builders who take this drug say that it doesn't do much. The only feature that has been consistently seen is a slight increase in weight. But since bodybuilders take so many other drugs, it's hard to know which drug is responsible. Testosterone has moderate anabolic properties but is also a potent androgenic agent. Andriol is taken orally at doses of 25-200 mg per day. However, most body builders see no effects at lower doses and even at doses close to 400mg/day the effects are minimal at best.