Norethisterone (INN, BAN), also known as Norethindrone (USAN) (brand names Micronor, AYGESTIN, numerous others) is a synthetic progestational hormone (progestin) with actions similar to those of progesterone but functioning as a more potent inhibitor of ovulation. It has weak estrogenic and androgenic properties. The hormone has been used for the treatment of secondary amenorrhea, endometriosis, and abnormal uterine bleeding due to hormonal imbalance in the absence of organic pathology, such as submucous fibroids or uterine cancer. AYGESTIN® is not intended, recommended or approved to be used with oncomitant estrogen therapy in postmenopausal women for endometrial protection. Progestins diffuse freely into target cells and bind to the progesterone receptor. Target cells include the female reproductive tract, the mammary gland, the hypothalamus, and the pituitary. Once bound to the receptor, progestins slow the frequency of release of gonadotropin releasing hormone (GnRH) from the hypothalamus and blunt the pre-ovulatory LH surge. Allergic reaction could be: Itching or hives, swelling in your face or hands, swelling or tingling in your mouth or throat, chest tightness, trouble breathing.

Estradiol an aromatized C18 steroid with hydroxyl group at 3-beta- and 17-beta-position. Estradiol-17-beta is the most potent form of mammalian estrogenic steroids. In humans, it is produced primarily by the cyclic ovaries and the placenta. It is also produced by the adipose tissue of men and postmenopausal women. The 17-alpha-isomer of estradiol binds weakly to estrogen receptors (receptors, estrogen) and exhibits little estrogenic activity in estrogen-responsive tissues. Estradiol enters target cells freely (e.g., female organs, breasts, hypothalamus, pituitary) and interacts with a target cell receptor. When the estrogen receptor has bound its ligand it can enter the nucleus of the target cell, and regulate gene transcription which leads to formation of messenger RNA. The mRNA interacts with ribosomes to produce specific proteins that express the effect of estradiol upon the target cell. Estradiol is used for the treatment of urogenital symptoms associated with post-menopausal atrophy of the vagina (such as dryness, burning, pruritus and dyspareunia) and/or the lower urinary tract (urinary urgency and dysuria). Estradiol is marketed under the brand name Climara (among others), indicated for: the treatment of moderate to severe vasomotor symptoms due to menopause, treatment of symptoms of vulvar and vaginal atrophy due to menopause, treatment of hypoestrogenism due to hypogonadism, castration or primary ovarian failure and prevention of postmenopausal osteoporosis.

Testosterone is a steroid sex hormone found in both men and women. In men, testosterone is produced primarily by the Leydig (interstitial) cells of the testes when stimulated by luteinizing hormone (LH). It functions to stimulate spermatogenesis, promote physical and functional maturation of spermatozoa, maintain accessory organs of the male reproductive tract, support development of secondary sexual characteristics, stimulate growth and metabolism throughout the body and influence brain development by stimulating sexual behaviors and sexual drive. In women, testosterone is produced by the ovaries (25%), adrenals (25%) and via peripheral conversion from androstenedione (50%). Testerone in women functions to maintain libido and general wellbeing. Testosterone exerts a negative feedback mechanism on pituitary release of LH and follicle-stimulating hormone (FSH). Testosterone may be further converted to dihydrotestosterone or estradiol depending on the tissue. The effects of testosterone in humans and other vertebrates occur by way of two main mechanisms: by activation of the androgen receptor (directly or as DHT), and by conversion to estradiol and activation of certain estrogen receptors. Free testosterone (T) is transported into the cytoplasm of target tissue cells, where it can bind to the androgen receptor, or can be reduced to 5α-dihydrotestosterone (DHT) by the cytoplasmic enzyme 5α-reductase. DHT binds to the same androgen receptor even more strongly than T, so that its androgenic potency is about 2.5 times that of T. The T-receptor or DHT-receptor complex undergoes a structural change that allows it to move into the cell nucleus and bind directly to specific nucleotide sequences of the chromosomal DNA. The areas of binding are called hormone response elements (HREs), and influence transcriptional activity of certain genes, producing the androgen effects. Testosterone is used as hormone replacement or substitution of diminished or absent endogenous testosterone. Use in males: For management of congenital or acquired hypogonadism, hypogonadism associated with HIV infection, and male climacteric (andopause). Use in females: For palliative treatment of androgen-responsive, advanced, inoperable, metastatis (skeletal) carcinoma of the breast in women who are 1-5 years postmenopausal; testosterone esters may be used in combination with estrogens in the management of moderate to severe vasomotor symptoms associated with menopause in women who do not respond to adequately to estrogen therapy alone.

Trestolone is a synthetic androgen that inhibits the release of follicle-stimulating hormone and impairs spermatogenesis. Luteinizing hormone is also suppressed, which cuts production of testosterone. The azoospermia and oligospermia are reversible after discontinuation of trestolone. Trestolone has androgenic and anabolic properties and loss of secondary sex characteristics is not seen. Like testosterone, trestolone undergoes enzymatic aromatization to an estrogen. The use of trestolone instead of testosterone for androgen replacement therapy could have health-promoting effects by reducing the occurrence of prostate disease. Trestolone had been in phase II clinical trial for the andropause control. However, this development was discontinued.

STANOLONE, also known as dihydrotestosterone, is a potent androgenic metabolite of testosterone and anabolic agent for systemic use. It may be used as a replacement of male sex steroids in men who have androgen deficiency, for example as a result of the loss of both testes, and also the treatment of certain rare forms of aplastic anemia which are or may be responsive to anabolic androgens.

Desoxycorticosterone pivalate (DOCP) is a mineralocorticoid hormone and an analog of desoxycorticosterone. DOCP is a long-acting ester of desoxycorticosterone acetate (DOCA) which is recognized as having the same qualitative effects as the natural mineralocorticoid hormone aldosterone. It’s used as Percorten-V for replacement therapy for the mineralocorticoid deficit in dogs with primary adrenocortical insufficiency. Percorten-V is only available in the U.S., Canada, Australia and recently, Denmark. Percorten was originally developed for the treatment of Addison's disease in humans but the demand for it decreased significantly once Florinef was available. Unaware that their product was being prescribed “off-label” for the treatment of canine Addison’s Disease and faced with a decreased demand for Percorten, the manufacturer *almost* discontinued production until the veterinary community rose up and voiced their distress. Field trials were run and the FDA approved the use of Percorten-V (the "v" is for veterinary). DOCP like other adrenocorticoid hormones is thought to act by controlling the rate of synthesis of proteins. It reacts with receptor proteins in the cytoplasm to form a steroid-receptor complex. This complex moves into the nucleus, where it binds to chromatin that result in genetic transcription of cellular DNA to messenger RNA. The steroid hormones appear to induce transcription and synthesis of specific proteins, which produce the physiologic effects seen after administration. The most important effect of DOCP is to increase the rate of renal tubular absorption of sodium. This effect is seen most intensely in the thick portion of the ascending limb of the loop of Henle. It also increases sodium absorption in the proximal convoluted tubule but this effect is less important in sodium retention. Chloride follows the sodium out of the renal tubule. Another important effect of DOCP is enhanced renal excretion of potassium. This effect is driven by the resorption of sodium that pulls potassium from the extracellular fluid into the renal tubules, thus promoting potassium excretion.

Methenolone (also known as primobolan) was described in 1960. Squibb Company began producing injectable drug in 1962. Methenolone originally was prescribed in case of muscle loss after operations, infections, long-term illnesses, aggressive therapy with corticoids or malnutrition, and in some cases it was used to treat osteoporosis and breast cancer. Methenolone was commonly used to promote weight gain in infants, weighing less than normal, without any side effects. Methenolone is an anabolic steroid, modification of dihydrotestosterone (DHT) with weak androgenic activity and a moderate anabolic effect. A notable trait of methenolone is that it can firmly bind to androgen receptors, stronger than testosterone. Adult doses for the treatment of aplastic anemia are usually in a range of 1–3 mg/kg per day. Adverse side effects include fluid and electrolyte retention, hypercalcaemia, increased bone growth and skeletal weight. In men, additional side priapism, azoospermia, hirsutism, male pattern baldness, acne andoedema. In women, side effects include virilization, amenorrhoea, menstrual irregularities, suppressed lactation, and increased libido. In children, side effects may include virilization symptoms. Metenolone may enhance effects of antidiabetics, ciclosporin, levothyroxine, warfarin. Resistance to the effects of neuromuscular blockers may occur, and metenolone also has the potential to interfere with glucose tolerance and thyroidfunction tests. Metenolone enanthate (methenolone enanthate) is an ester derivative of methenolone sold commonly under the brand names Primobolan (tablet form) orPrimobolan Depot (injectable). When it interacts with the aromatase enzyme it does not form any estrogens. It is used by people who are very susceptible to estrogenic side effects, having lowerestrogenic properties than nandrolone. This trait makes primobolan to be a good fat burner. Primobolan does not convert into estradiol. As an anabolic steroid, the use of metenolone is banned from use in sports governed by the World Anti-Doping Agency. Belarusian shot putter Nadzeya Ostapchuk was stripped of her gold medal after testing positive for metenolone at the London 2012 Olympic Games. She has been excluded from future IOC events. The NBA and NBPA also banned the use of methenolone under the Anti-Drug Program. In February 2013, Hedo Türkoğlu of the Orlando Magic was suspended for 20 games without pay by the league after testing positive for methenolone. In December 2013, Natalia Volgina was stripped of her 2013 Old Mutual Two Oceans Marathon title and received a two-year competition ban, subsequent to a final guilty verdict for using the steroid Metenolone.