Dihydrotestosterone is an endogenous androgen sex steroid and hormone. The enzyme 5α-reductase catalyzes the formation of DHT from testosterone in certain tissues including the prostate gland, seminal vesicles, epididymides, skin, hair follicles, liver, and brain. This enzyme mediates reduction of the C4-5 double bond of testosterone. DHT may also be synthesized from progesterone and 17α-hydroxyprogesterone via the androgen backdoor pathway in the absence of testosterone. Relative to testosterone, DHT is considerably more potent as an agonist of the androgen receptor (AR).
Nilutamide, sold under the brand names Nilandron and Anandron, is a nonsteroidal antiandrogen (NSAA) which is used in the treatment of prostate cancer. It has also been studied as a component of feminizing hormone therapy for transgender women and to treat acne and seborrhea in women. It is taken by mouth.
Dehydroepiandrosterone sulfate, abbreviated as DHEA sulfate or DHEA-S, also known as androstenolone sulfate, is an endogenous androstane steroid that is produced by the adrenal cortex. It is the 3β-sulfate ester and a metabolite of dehydroepiandrosterone (DHEA) and circulates in far greater relative concentrations than DHEA. The steroid is hormonally inert and is instead an important neurosteroid and neurotrophin.
Medroxyprogesterone (MP), is a progestin which is not used medically. A derivative, medroxyprogesterone acetate (MPA), is used as a medication in humans, and is far more widely known in comparison. Medroxyprogesterone is sometimes used as a synonym for medroxyprogesterone acetate, and what is almost always being referred to when the term is used is MPA and not medroxyprogesterone.
Allopregnanolone is a naturally occurring neurosteroid which is made in the body from the hormone progesterone. As a medication, allopregnanolone is referred to as brexanolone, sold under the brand name Zulresso, and used to treat postpartum depression. It is given by injection into a vein.
Alfaxalone, also known as alphaxalone or alphaxolone and sold under the brand name Alfaxan, is a neuroactive steroid and general anesthetic which is used currently in veterinary practice as an induction agent for anesthesia and as an injectable anesthetic. Though it is more expensive than other induction agents, it often preferred due to the lack of depressive effects on the cardiovascular system. The most common side effect seen in current veterinary practice is respiratory depression when Alfaxan is administered concurrently with other sedative and anesthetic drugs; when premedications aren't given, veterinary patients also become agitated and hypersensitive when waking up.
L-838,417 is an anxiolytic drug used in scientific research. It has similar effects to benzodiazepine drugs, but is structurally distinct and so is classed as a nonbenzodiazepine anxiolytic. The compound was developed by Merck, Sharp and Dohme.
Pregnanolone, also known as eltanolone, is an endogenous inhibitory neurosteroid which is produced in the body from progesterone. It is closely related to allopregnanolone, which has similar properties.
Tetrahydrodeoxycorticosterone, also referred to as allotetrahydrocorticosterone, is an endogenous neurosteroid. It is synthesized from the adrenal hormone deoxycorticosterone by the action of two enzymes, 5α-reductase type I and 3α-hydroxysteroid dehydrogenase. THDOC is a potent positive allosteric modulator of the GABAA receptor, and has sedative, anxiolytic and anticonvulsant effects. Changes in the normal levels of this steroid particularly during pregnancy and menstruation may be involved in some types of epilepsy and premenstrual syndrome, as well as stress, anxiety and depression.
Normethandrone, also known as methylestrenolone or methylnortestosterone and sold under the brand name Metalutin among others, is a progestin and androgen/anabolic steroid (AAS) medication which is used in combination with an estrogen in the treatment of amenorrhea and menopausal symptoms in women. It is taken by mouth.
Trimegestone, sold under the brand names Ondeva and Totelle among others, is a progestin medication which is used in menopausal hormone therapy and in the prevention of postmenopausal osteoporosis. It was also under development for use in birth control pills to prevent pregnancy, but ultimately was not marketed for this purpose. The medication is available alone or in combination with an estrogen. It is taken by mouth.
In pharmacology, GABAA receptor positive allosteric modulators, also known as GABAkines or GABAA receptor potentiators, are positive allosteric modulator (PAM) molecules that increase the activity of the GABAA receptor protein in the vertebrate central nervous system.
20α-Dihydroprogesterone (20α-DHP), also known as 20α-hydroxyprogesterone (20α-OHP), is a naturally occurring, endogenous progestogen. It is a metabolite of progesterone, formed by the 20α-hydroxysteroid dehydrogenases (20α-HSDs) AKR1C1, AKR1C2, and AKR1C3 and the 17β-hydroxysteroid dehydrogenase (17β-HSD) HSD17B1. 20α-DHP can be transformed back into progesterone by 20α-HSDs and by the 17β-HSD HSD17B2. HSD17B2 is expressed in the human endometrium and cervix among other tissues. In animal studies, 20α-DHP has been found to be selectively taken up into and retained in target tissues such as the uterus, brain, and skeletal muscle.
A steroidogenesis inhibitor, also known as a steroid biosynthesis inhibitor, is a type of drug which inhibits one or more of the enzymes that are involved in the process of steroidogenesis, the biosynthesis of endogenous steroids and steroid hormones. They may inhibit the production of cholesterol and other sterols, sex steroids such as androgens, estrogens, and progestogens, corticosteroids such as glucocorticoids and mineralocorticoids, and neurosteroids. They are used in the treatment of a variety of medical conditions that depend on endogenous steroids.
Chloroethynylnorgestrel is a steroidal progestin of the 19-nortestosterone group related to norgestrel that was investigated as an oral contraceptive in the 1970s but was never marketed.
BOMT, also known by its developmental code name Ro 7-2340 and as 6α-bromo-4-oxa-17α-methyl-5α-dihydrotestosterone, is a synthetic steroidal antiandrogen which was first developed in 1970 and was never marketed for medical use. It is the 6α-brominated, 4-oxygenated, and 17α-methylated derivative of the androgen dihydrotestosterone (DHT). Along with benorterone, cyproterone, and flutamide, BOMT was among the earliest antiandrogens to be developed and extensively studied, although it is less well-documented in comparison to the others. BOMT has been investigated clinically in the treatment of benign prostatic hyperplasia, though development for this use did not continue. There was also interest in BOMT for the potential applications of acne, pattern hair loss, and possibly prostate cancer, but it was not developed for these indications either.
Dienolone, or nordienolone, also known as 19-nor-δ9(10)-testosterone, δ9(10)-nandrolone, or estra-4,9(10)-dien-17β-ol-3-one, is a synthetic anabolic-androgenic steroid (AAS) of the 19-nortestosterone group that was never marketed. It has been found to possess slightly lower affinity for the androgen receptor (AR) and progesterone receptor (PR) relative to nandrolone in rat and rabbit tissue bioassays, whereas trenbolone was found to possess the same affinity for the AR as dienolone but several-fold increased affinity for the PR. Dienedione is thought to be a prohormone of dienolone, while methyldienolone and ethyldienolone are orally active 17α-alkylated AAS derivatives of dienolone. In contrast, dienogest, the 17α-cyanomethyl derivative of dienolone, is a potent progestogen and antiandrogen.
ORG-2058, also known as 16α-ethyl-21-hydroxy-19-norprogesterone, is a progestin of the 19-norprogesterone group which was never marketed. It has high affinity for the progesterone receptor and has been used in scientific research to study the role of the progesterone receptor in the body. The drug has no affinity for the estrogen receptor or the glucocorticoid receptor and has slight affinity for the mineralocorticoid receptor, but less than that of progesterone.
17α-Allyl-19-nortestosterone, also known as 3-ketoallylestrenol or as 17α-allylestr-4-en-17β-ol-3-one, is a progestin which was never marketed. It is a combined derivative of the anabolic–androgenic steroid and progestogen nandrolone (19-nortestosterone) and the antiandrogen allyltestosterone (17α-allyltestosterone). The drug is a major active metabolite of allylestrenol, which is thought to be a prodrug of 17α-allyl-19-nortestosterone.
Posovolone is a synthetic neurosteroid which was under development as a sedative/hypnotic medication for the treatment of insomnia. It is orally active and acts as a GABAA receptor positive allosteric modulator. In animals, posovolone shows anticonvulsant, anxiolytic-like, ataxic, and sleep-promoting effects and appeared to produce effects similar to those of pregnanolone. Development of the agent was started by 1999 and appears to have been discontinued by 2007. In 2021, an INN was registered for posovolone with the descriptor of "antidepressant". Posovolone was originally developed by Purdue Pharma.
