For this reason, and due to the unknown health effects and safety of testosterone therapy, its use may be inappropriate. A subsequent 2017 systematic review and meta-analysis of studies including over 3,000 postmenopausal women with HSDD similarly found that short-term transdermal testosterone therapy was effective in improving multiple domains of sexual function. The changes were more pronounced with oral testosterone undecanoate than with parenteral routes, such as transdermal testosterone. These included decreased levels of total cholesterol, triglycerides, and high-density lipoprotein (HDL) cholesterol, and increased levels of low-density lipoprotein (LDL) cholesterol. Because of a lack data to support its efficacy and safety, the Endocrine Society recommends against the routine use of testosterone in women to treat low androgen levels due to hypopituitarism, adrenal insufficiency, surgical removal of the ovaries, high-dose corticosteroid therapy, or other causes. To take advantage of its virilizing effects, testosterone, often shortened to T, is administered to transgender men and other transmasculine individuals as part of masculinizing hormone therapy, titrated to clinical effect with a "target level" of the average male's testosterone level.
Estrogens can reduce the effects of testosterone by increasing the hepatic production and in turn circulating levels of sex hormone-binding globulin (SHBG), a carrier protein that binds to and occupies androgens like testosterone and DHT, and thereby reducing free concentrations of these androgens. However, estradiol exerts negative feedback on the hypothalamic–pituitary–gonadal axis and, for this reason, prevention of its formation can reduce this feedback and disinhibit gonadal production of testosterone, which in turn can increase levels of endogenous testosterone. As only a very small fraction of testosterone is converted into estradiol, this does not affect testosterone levels, but it can prevent estrogenic side effects like gynecomastia that can occur when testosterone is administered at relatively high dosages. On the other hand, 5α-reductase inhibitors may prevent or reduce adverse androgenic side effects of testosterone like scalp hair loss, oily skin, acne, and seborrhea.
There have been reports of misuse of men taking higher doses of legally obtained testosterone than prescribed and continuing testosterone despite adverse events or against medical advice. Changes in insulin sensitivity or glycemic control may occur in patients treated with androgens. The following adverse reactions have been identified during post-approval use of AVEED. In these clinical trials, the dose and dose frequency of intramuscular testosterone undecanoate varied from 750 mg to 1000 mg, and from every 9 weeks to every 14 weeks. A total of 725 hypogonadal men received intramuscular testosterone undecanoate in a total of 7 controlled clinical trials. 750 mg/3 mL (250 mg/mL) testosterone undecanoate sterile injectable solution is provided in an amber glass, single use vial with silver-colored crimp seal and gray plastic cap.
The FDA has required that testosterone pharmaceutical labels include warning information about the possibility of an increased risk of heart attacks and stroke. The high doses of testosterone required to increase sexual desire in women may have a significant risk of masculinization with long-term therapy. The FDA has required that labels on testosterone include warnings about increased risk of heart attacks and stroke.
Endogenous androgens, including testosterone and dihydrotestosterone (DHT) are responsible for the normal growth and development of the male sex organs and for maintenance of secondary sex characteristics. Of the153 patients enrolled in the pivotal clinical study utilizing AVEED, 26 (17.0%) were over 65 years of age. Reduced fertility is observed in some men taking testosterone replacement therapy. Hypertension was observed in pregnant female rats and their offspring exposed to doses approximately twice those used for testosterone replacement therapy.
The mean DHT to testosterone ratios ranged from 0.05 to 0.07. The major active metabolites of testosterone are estradiol and DHT. Testosterone undecanoate was nearly undetectable 42 days following injection of AVEED. Testosterone undecanoate is metabolized to testosterone via ester cleavage of the undecanoate group. Approximately 40% of testosterone in plasma is bound to SHBG, 2% remains unbound (free), and the rest is loosely bound to albumin and other proteins.

Gender : Male