TestosteroneTestosterone is the primary male sex hormone and an anabolic steroid. In male humans, testosterone plays a key role in the development of male reproductive tissues such as testes and prostateas well as promoting secondary sexual characteristics such as increased muscle and bone mass, and the growth of body hair. Testo xl wikipedia is a steroid from the androstane class containing a keto and hydroxyl groups at the three and seventeen positions respectively. It is biosynthesized in several steps from cholesterol and is converted in the liver to inactive metabolites. On average, testo xl wikipedia adult males, levels of testosterone are about 7 to 8 times as great as in adult females. In addition to its role as a getting testosterone online hormone, testosterone is used as a medicationfor instance in the treatment of low testo xl wikipedia levels in men and breast cancer in women. It is also used illicitly to enhance physique and performancefor instance in athletes.
Testosterone (medication) - Wikipedia
Testosterone is a medication and naturally occurring steroid hormone. Common side effects of testosterone include acne , swelling , and breast enlargement in men. Testosterone was first isolated in The primary use of testosterone is the treatment of males with too little or no natural testosterone production, also termed hypogonadism or hypoandrogenism androgen deficiency.
It is used to maintain serum testosterone levels in the normal male range. Decline of testosterone production with age has led to interest in testosterone supplementation.
Testosterone deficiency also termed hypotestosteronism or hypotestosteronemia is an abnormally low testosterone production. It may occur because of testicular dysfunction primary hypogonadism or hypothalamic—pituitary dysfunction secondary hypogonadism and may be congenital or acquired. Testosterone levels may decline gradually with age.
To take advantage of its virilizing effects, testosterone is administered to transgender men as part of masculinizing hormone therapy ,  titrated to clinical effect with a "target level" of the average male's testosterone level.
Testosterone supplementation in low doses is effective in the short-term for hypoactive sexual desire disorder in women. Although testosterone is effective in improving sexual function in postmenopausal women, this does not appear to be the case similarly in premenopausal women.
Testosterone is used as a form of doping among athletes in order to improve performance. Anabolic—androgenic steroids AAS , including testosterone and its esters, have also been taken to enhance muscle development, strength, or endurance. They do so directly by increasing the muscles' protein synthesis. As a result, muscle fibers become larger and repair faster than the average person's. After a series of scandals and publicity in the s such as Ben Johnson's improved performance at the Summer Olympics , prohibitions of AAS use were renewed or strengthened by many sports organizations.
Steroid use once again came into the spotlight recently as a result of Canadian professional wrestler Chris Benoit 's double murder-suicide in ; however, there is no evidence implicating steroid use as a factor in the incident. Some female athletes may have naturally higher levels of testosterone than others, and may be asked to consent to sex verification and either surgery or drugs to decrease testosterone levels.
A number of methods for detecting testosterone use by athletes have been employed, most based on a urine test. In some testing programs, an individual's own historical results may serve as a reference interval for interpretation of a suspicious finding. Another approach being investigated is the detection of the administered form of testosterone, usually an ester, in hair. Exogenous testosterone may cause suppression of spermatogenesis in men, leading to, in some cases, reversible infertility.
Other side effects include increased hematocrit , which can require venipuncture in order to treat, and exacerbation of sleep apnea. The FDA stated in that neither the benefits nor the safety of testosterone have been established for low testosterone levels due to aging.
Adverse effects of testosterone supplementation may include increased cardiovascular events including strokes and heart attacks and deaths based on three peer-reviewed studies involving men taking testosterone replacement. Up to the year , studies had not shown any effect on the risk of death, prostate cancer or cardiovascular disease ;   more recent studies, however, do raise concerns.
Testosterone in the presence of a slow-growing prostate cancer is assumed to increase its growth rate. However, the association between testosterone supplementation and the development of prostate cancer is unproven.
It may accelerate pre-existing prostate cancer growth in individuals who have undergone androgen deprivation. Ethnic groups have different rates of prostate cancer. Testosterone is contraindicated in pregnancy and not recommended during breastfeeding. Aromatase inhibitors like anastrozole prevent the conversion of testosterone into estradiol by aromatase.
Inhibitors and inducers of cytochrome P enzymes like CYP3A4 have been associated with little or no effect on circulating testosterone levels. Antiandrogens like cyproterone acetate , spironolactone , and bicalutamide can block the androgenic and anabolic effects of testosterone. Testosterone is a high affinity ligand for and agonist of the nuclear androgen receptor AR.
In contrast to the case of testosterone, such potentiation occurs to a reduced extent or not at all with most synthetic AAS as well as with DHT , and this is primarily responsible for the dissociation of anabolic and androgenic effects with these agents. The ARs are expressed widely throughout the body, including in the penis , testicles , epididymides , prostate gland , seminal vesicles , fat , skin , bone , bone marrow , muscle , larynx , heart , liver , kidneys , pituitary gland , hypothalamus , and elsewhere throughout the brain.
Testosterone is not active orally except in extremely high dosages due to poor absorption and extensive first-pass metabolism. Although testosterone itself is not used orally, testosterone undecanoate is approved and used orally. The oral bioavailability of testosterone is very low and virtually negligible. The elimination half-life of testosterone varies depending on the route of administration and formulation and on whether or not it is esterified.
Whereas the terminal half-life of unesterified testosterone administered via intramuscular injection is very short at only around 10 minutes, the terminal half-lives of intramuscular testosterone esters are far longer. The absorption half-life of subdermal testosterone implants is 2. Testosterone and its metabolites are eliminated in the urine. All synthetic AAS are derivatives of testosterone. This is almost always in ester form; for instance, in the case of nandrolone, as nandrolone decanoate or nandrolone phenylpropionate.
Testosterone was first isolated and synthesized in In the US in the s, companies and figures in the popular media have heavily marketed notions of "andropause" as something parallel to menopause ; these notions have been rejected by the medical community. Handelsman, writing in a editorial in the Journal of the American Geriatrics Society , it appears that this condition is overdiagnosed and overtreated.
Testosterone is marketed under a large number of brand names throughout the world. And the following ester prodrugs of testosterone are available in the United States in oil solutions for intramuscular injection: Unmodified testosterone was also formerly available for intramuscular injection but was discontinued.
Testosterone cypionate and testosterone enanthate were formerly available in combination with estradiol cypionate and estradiol valerate , respectively, under the brand names Depo-Testadiol and Ditate-DS, respectively, as oil solutions for intramuscular injection, but these formulations have been discontinued.
Unlike in Europe , Canada , and much of the rest of the world, oral testosterone undecanoate is not available in the United States. Testosterone and its esters, along with other AAS, are prescription-only controlled substances in many countries throughout the world.
As of , a number of lawsuits are underway against manufacturers of testosterone, alleging a significantly increased rate of stroke and heart attack in elderly men who use testosterone supplementation. There are many known cases of doping in sports with testosterone and its esters by professional athletes. Testosterone has been used to treat depression in men who are of middle age with low testosterone. However, a review showed no benefit on the mood of the men with normal levels of testosterone or on the mood of the older men with low testosterone.
Testosterone replacement can significantly improve exercise capacity , muscle strength and reduce QT intervals in men with chronic heart failure CHF. Over the 3 to 6-month course of the studies reviewed, testosterone therapy appeared safe and generally effective, and ruling out prostate cancer the authors found no justification to absolutely restrict its use in men with CHF.
Testosterone, as esters such as testosterone undecanoate or testosterone buciclate, has been studied and promoted as a male contraceptive analogous to estrogen-based contraceptives in women. Otherwise considered an adverse effect of testosterone, reduced spermatogenesis can be further suppressed with the addition of a progestin such as norethisterone enanthate or levonorgestrel butanoate , improving the contraceptive effect.
Testosterone is under development in a low-dose intranasal formulation for the treatment of anorgasmia in women. Testosterone therapy may improve the management of type 2 diabetes.
From Wikipedia, the free encyclopedia. This article is about testosterone as a medication. For the natural hormone, see Testosterone. X Contraindicated Contraindicated due to teratogenic effects.
Ergogenic use of anabolic steroids and Anabolic—androgenic steroids abuse. Testosterone and the cardiovascular system. List of investigational sexual dysfunction drugs.
Williams Textbook of Endocrinology. American Society of Health-System Pharmacists. Archived from the original on August 20, Retrieved September 3, Archived from the original on March 5, Retrieved March 5, Anabolic Steroids and the Athlete 2 ed. Archived from the original on September 14, Translational Andrology and Urology. Archived PDF from the original on December 13, Retrieved December 8, Why, When, and How? Archived from the original on October 3, Retrieved October 3, The Western Journal of Medicine.
National Academies Press US. The Health in Men Study". Archived from the original on November 2, Retrieved October 31, Lyon-Martin Women's Health Services. Archived PDF from the original on November 30, Retrieved December 11, The Journal of Clinical Endocrinology and Metabolism.
The benefits and harms of systemic testosterone therapy in postmenopausal women with normal adrenal function: Int J Womens Health. Archived from the original on May 27,