The main androgen in the body is testosterone. Species of cells in the testis, ovary, and adrenal cortex produce endogenous testosterone. In the treatment of either congenital or acquired hypogonadism, testosterone is employed. The best exogenous androgen for the palliative therapy of breast cancer in postmenopausal women is testosterone. In 1938, testosterone was in use, and the FDA gave its approval in 1939. Since they have been used illegally, anabolic steroids, which are testosterone derivatives, are now considered controlled substances. In 1991, testosterone, along with a number of anabolic steroids, was designated as a restricted substance. AndroGel, a testosterone cream developed by Uniumed Pharmaceuticals in the US, received FDA approval in 2000 for the treatment of testosterone, a condition that frequently causes mood, energy, and sexual dysfunctions, as well as a number of injury-related conditions like those suffered by severe burn and accident victims. AndroGel, a very popular form of testosterone, is sold all over the world under a few less well-known brand/trade names, most notably Testogel (produced in the UK by Laboratoires Besins and distributed by Bayer), Testim (produced in the US by Auxilium Pharmaceuticals, Inc.), and several generic variations frequently marketed as testosterone cream or gel.

The target body regions for testosterone cream’s transdermal delivery system are the same or very comparable to those for injections and other testosterone delivery methods. More specifically, testosterone cream absorbs best when applied to heavily muscled body parts, just like testosterone injections do. Since there are more testosterone-absorbing capillaries at the site of application when there is more muscle, testosterone can enter the bloodstream more quickly.