The androgen testosterone, often known as the male sex hormone, is responsible for the male reproductive system’s masculine traits. The Leydig cells, which are situated between the seminiferous tubules in the male testes, are where it is largely made. The adrenal hormones dehydroepiandrosterone (DHEA), dehydroepiandrosterone sulfate (DHEA-S), androstenedione, and androstanediol are converted in the peripheral tissues to testosterone and estrogen. It is also produced indirectly in lower amounts in the adrenal glands. In females, the ovaries are where testosterone is made. Handelsman, D.J., “Androgen Physiology, Pharmacology, Use and Misuse”, Endotext. October 2020. Available: https://www.ncbi.nlm.nih.gov/books/NBK279000/Antoniou-Tsigkos, A., Zapanti, E., Ghizzoni, L., Mastorakos, G.,”Adrenal Androgens”, Endotext. January 2019. Available: https://www.ncbi.nlm.nih.gov/books/NBK278929/
Even though testosterone serves primarily to develop secondary characteristics in men, it serves other essential functions within the human body. Some additional roles performed by testosterone include the following:Tyagi, V., Scordo, M., Yoon, R.S., Liporace, F.A., Greene, L.W., “Revisiting the role of testosterone: Are we missing something?”, Reviews in Urology, vol. 19 issue 1, pp. 16-24. Available: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5434832/Coviello, A.D., Kaplan, B., Lakshman, K.M., Chen, T., Singh, A.B., Bhasin, S., “Effects of Graded Doses of Testosterone on Erythropoiesis in Healthy Young and Older Men”, Journal of Clinical Endocrinology and Metabolism, vol.93 issue 3, pp.914-919. Available: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2266950/“Additional Studies of Testosterone Therapy”, Testosterone and Aging: Clinical Research Directions. Available: https://www.ncbi.nlm.nih.gov/books/NBK216178/
- In the skeletal system, testosterone aids in bone maintenance as well as growth. By decreasing the amounts of bone osteoclasts, testosterone helps decrease bone resorption and, consequently, increase bone density. This action is performed through the aromatization of testosterone to estradiol, which then activates alpha and beta receptors on the bone. Additionally, testosterone is converted to the active metabolite dihydrotestosterone (DHT) by means of the enzyme 5-alpha reductase; DHT is two to three times more potent than testosterone and it stimulates the osteoblasts within the bones and promote bone growth.
- In the muscles, testosterone helps in the development of lean body mass, muscle volume, muscle strength, and the loss of fatty tissue.
- Studies have indicated that testosterone is beneficial in the production of red blood cells. This effect is generally seen more in older rather than younger men. However, this may also lead to erythrocytosis as an adverse effect in men receiving exogenous testosterone supplements.
- Through mechanisms that have not been fully defined, testosterone has been shown to play a role in individuals’ mood and mental state. Research studies carried out indicated that men suffering from low testosterone had an improvement in their cognitive abilities as well as mood after receiving exogenous testosterone supplements.
Generally, testosterone levels do not begin to increase until around the age of puberty. Once puberty is achieved, testosterone levels increase significantly until about the third or fourth decade of life, after which they begin to decrease gradually. When this occurs, males may manifest with varied symptoms such as loss of body hair, decreased bone density, decreased libido and erectile dysfunction, decreased lean body mass, and increased body fat, among other symptoms. Individuals manifesting signs and symptoms of low testosterone levels may benefit from exogenous testosterone administration.Rivas, A.M., Mulkey, Z., Lado-Abeal, J., Yarbrough, M., “Diagnosing and managing low serum testosterone”, Proceedings (Baylor University Medical Center), vol.27 issue 4, pp. 312-324. October 2014. Available: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4255853/
There are certain conditions under which exogenous testosterone should not be administered or, if necessary, administered with extreme caution. Some of these indications include the following:Petering, P.C., Brooks, N.A., “Testosterone Therapy: Review of Clinical Applications”, American Family Physician, vol.96 issue 7 pp.441-449. Available: https://www.aafp.org/afp/2017/1001/p441.htmlCunha, J.P., “Testosterone”, RxList. Available: https://www.rxlist.com/consumer_testosterone-medication/drugs-condition.html
- Prostate cancer: Administering supplements containing exogenous testosterone is strictly prohibited in this situation. This is so because, in men who already have prostate cancer, testosterone can encourage the growth of malignant cells.
- Polycythemia Vera: Exogenous testosterone supplements shouldn’t be given to anyone with this blood dyscrasia. Hematocrit levels are higher than normal in those with polycythemia; testosterone administration may raise these levels even further, which could make symptoms worse for those with this illness.
- Breast cancer:Exogenous testosterone administration is absolutely against the rules since, like prostate cancer, breast cancer is hormone-dependent.
- Venous thromboembolism:This is a relative contraindication to the use of exogenous testosterone; it has been documented that some people who take testosterone supplements develop deep vein thrombosis and pulmonary embolism.
- Cardiovascular disease:Given that some persons have experienced strokes after receiving testosterone replacement treatment, caution should be taken when giving testosterone supplements to people who have a history of coronary artery disease or myocardial infarction.
The Food and Drug Administration (FDA) classifies testosterone supplements under category X. Studies have revealed embryonic abnormalities and signs of greater fetal risks in women who take testosterone supplements when they are pregnant. Any potential benefits of giving it to pregnant women exceed the dangers of developing serious fetal defects by a wide margin. If a woman becomes pregnant, testosterone replacement therapy should be stopped promptly. Additionally, testosterone and its metabolites should not be given to nursing mothers because they excrete them in breast milk. “Testosterone Pregnancy and Breastfeeding Warnings”. Available: https://www.drugs.com/pregnancy/testosterone.html
Those taking exogenous testosterone supplements run the risk of experiencing a variety of negative effects. Mild to possibly fatal symptoms can result from these side effects. Some possible adverse reactions that could occur while on exogenous testosterone therapy include, but are not limited to, the following:“Testosterone Injection”. Available: https://www.drugs.com/testosterone.html
- Women may experience signs of virilization such as male-pattern hair growth, enlarged clitoris, and a deep or hoarse voice, among others.
- Urinary retention and worsening of other features associated with benign prostatic hypertrophy (BPH).
- Features of myocardial infarction such as chest pain, cough, wheezing, shortness of breath, and coughing up blood.
- Abdominal pain and loss of appetite.
- Generalized body itching, jaundice, and clay-colored stools.
- Features of deep venous thrombosis such as pain, warmth, swelling, or redness in one or both legs.
- Features of fluid retention such as weight gain and swelling of the ankles or feet.
Store this medication in its original container at 68°F to 77°F (20°C to 25°C) and away from heat, moisture and light. Keep all medicine out of the reach of children. Throw away any unused medicine after the beyond-use date. Do not flush unused medications or pour down a sink or drain.