Drug Insight: testosterone preparations

Abstract

Testosterone has been used for substitution therapy in testicular and hypothalamopituitary diseases for almost six decades, with injectable testosterone esters and implanted testosterone pellets being the mainstay of treatment. Growing interest in the possible use of testosterone in nonclassical situations such as male contraception, aging (late-onset hypogonadism), muscle-wasting conditions like HIV, erectile dysfunction, and female hypoactive sexual disorder has stimulated research, leading to the development of several new modes of administration of testosterone. Transdermal patches, gels, mucoadhesive sustained-release buccal tablets and long-acting testosterone esters are designed to provide testosterone levels that approximate normal physiologic levels, to improve patient acceptability, and to further increase the number of treatment options available. In this Review, we briefly describe the chemistry, mechanism of action, and metabolism of testosterone. We then discuss the pharmacokinetics, advantages, and disadvantages of various formulations and summarize the various preparations currently available.

Urologic complications of HIV and AIDS

“…99 The use of testosterone in muscle-wasting disorders such as HIV has also been suggested as a treatment option. 100 Effective treatment of ED can increase the risk of spreading HIV. 101 Benotschet al 102 have shown that men who took phosphodiesterase-5 inhibitors had higher rates of sexually risky behavior.…”

Androgen receptor variation affects prostate cancer progression and drug resistance

“…Cytosolic AR is sequestered by heat shock proteins (HSPs) until it binds to androgens (3, 4). Ligand binding is a function of the conformation of the ligand-binding pocket, which prefers dihydrotestosterone (DHT) and testosterone (to a lesser extent) while excluding weaker androgens and non-androgens (3, 4).…”

“…Ligand binding is a function of the conformation of the ligand-binding pocket, which prefers dihydrotestosterone (DHT) and testosterone (to a lesser extent) while excluding weaker androgens and non-androgens (3, 4). Following ligand binding, the AR undergoes a conformational change in which helix 12 covers the hormone-binding pocket, causing the AR to adopt the active conformation (5).…”

Male hypogonadism: The unrecognized cardiovascular risk factor

“…The gel can be put on at any time. 33 The majority of oral preparations have been reconstituted to achieve the maximum anabolic effects, without aromatization to estrogens. Most of the oral preparations also have unpredictable androgenic activity, and have been associated with a high degree of liver toxicity (cholestasis, cystic disease, and hepatoma).…”

“…Testosterone must be given in a form that can be aromatized to estradiol to cause gynecomastia, which is more typical of the IM injections. 33,34 …”