Drostanolone propionate

Drostanolone propionate, or dromostanolone propionate, sold under the brand names Drolban, Masteril, and Masteron among others, is an androgen and anabolic steroid (AAS) medication which was used to treat breast cancer in women but is now no longer marketed. It is given by injection into muscle.

Side effects of drostanolone propionate include symptoms of masculinization like acne, increased hair growth, voice changes, and increased sexual desire. It has no risk of liver damage. The drug is a synthetic androgen and anabolic steroid and hence is an agonist of the androgen receptor (AR), the biological target of androgens like testosterone and dihydrotestosterone (DHT). It has moderate anabolic effects and weak androgenic effects, which give it a mild side effect profile and make it especially suitable for use in women. The drug has no estrogenic effects. Drostanolone propionate is an androgen ester and a long-lasting prodrug of drostanolone in the body.

Drostanolone propionate was first described in 1959 and was introduced for medical use in 1961. In addition to its medical use, drostanolone propionate is used to improve physique and performance. The drug is a controlled substance in many countries and so non-medical use is generally illicit.

Medical uses
The principal clinical indication of drostanolone propionate in the United States as well as international markets was the treatment of advanced inoperable breast cancer in women.

Hormonal treatment is part of the complex therapy for some kind of tumors, particularly the ones associated with hormone-active tissues like breast or prostate cancer. Some types of breast cancer cells, expressing estrogen receptors (called ER+ cancers), use estrogen for their growth and dissemination. That is why drugs that block estrogen receptors or decrease their expression on the cell membrane, antiestrogens, could limit the tumor spread and size. Drostanolone propionate has been FDA approved as an antiestrogenic drug for the treatment of breast cancer. By the time of its release, there were not many alternatives for patients with breast cancer and drostanolone propionate was a revolution for these patients. As it has lower androgenic rate compared to testosterone, the risk of virilization is much lighter. Due to this fact, women, who usually do not respond well to any AAS, were having much greater chance to survive cancer. Drostanolone propionate can also be used for breast tumors that do not respond well to other treatments or also as palliative care for advanced incurable tumors. The effects of the product depend of course on the dose and period of administration. The risk of virilization becomes greater with high doses and continuous administration period.

Non-medical uses
Drostanolone propionate is or has been used for physique- and performance-enhancing purposes by competitive athletes, bodybuilders, and powerlifters.

Side effects
Drostanolone propionate produces considerably less virilization in women compared to equal doses of testosterone propionate. However, since the given dosage for breast cancer was relatively high (200 mg/twice a week), mild virilization including oily skin, acne, voice deepening, hirsutism, and clitoral enlargement could still occur, and marked virilization could manifest with long-term therapy. The drug has no estrogenic activity and hence has no propensity for causing gynecomastia (in males) or fluid retention. Drostanolone propionate is not known to pose a risk of hepatotoxicity.

Pharmacodynamics
Drostanolone propionate is a prodrug of drostanolone. Like other AAS, drostanolone is an agonist of the androgen receptor (AR). It is not a substrate for 5α-reductase and is a poor substrate for 3α-hydroxysteroid dehydrogenase (3α-HSD), and therefore shows a high ratio of anabolic to androgenic activity. As a DHT derivative, drostanolone is not a substrate for aromatase and hence cannot be aromatized into estrogenic metabolites. While no data are available on the progestogenic activity of drostanolone, it is thought to have low or no such activity similarly to other DHT derivatives. Since the drug is not 17α-alkylated, it is not known to cause hepatotoxicity.

Drostanolone propionate, via its active form drostanolone, interacts with the AR and activates a cascade of genetic changes, including increased protein synthesis (anabolism) and decreased amino acid degradation (catabolism). It also induces a reduction or inhibition of prolactin or estrogen receptors in the breasts, which is linked to its antitumor effects.

Pharmacokinetics
Drostanolone propionate is not active via the oral route and must be administered via intramuscular injection. The elimination half-life of the drug via this route is approximately 2 days. It has a much longer elimination half-life via intramuscular injection than drostanolone. Drostanolone propionate is metabolized into drostanolone, which is the active form.

Chemistry
Drostanolone propionate, or drostanolone 17β-propionate, is a synthetic androstane steroid and a derivative of DHT. It is the C17β propionate (propanoate) ester of drostanolone, which itself is 2α-methyl-4,5α-dihydrotestosterone (2α-methyl-DHT) or 2α-methyl-5α-androstan-17β-ol-3-one.

History
Drostanolone and drostanolone propionate were first described in 1959. The related AAS oxymetholone and methasterone (methyldrostanolone) were first described in the same paper as well. Drostanolone propionate was introduced for medical use in the United States in 1961 and in Europe shortly thereafter.

Generic names
Drostanolone propionate is the generic name of the drug and its BANM, while dromostanolone propionate is the USAN and USP; there is no INN for this form. The generic name of the unesterified form of the drug is drostanolone or dromostanolone and the former is its INN, BAN, and DCF while there is no USAN.

Brand names
Drostanolone propionate was marketed under a variety of brand names including Drolban, Masterid, Masteril, Masteron, Masterone, Mastisol, Metormon, Permastril, and Prometholone.

Availability
Drostanolone propionate appears to no longer be marketed. It was previously available in the United States, Europe, and Japan. In Europe, it was specifically marketed in the United Kingdom, Germany, Belgium, France, Spain, Portugal, Italy, and Bulgaria.

Legal status
Drostanolone propionate, along with other AAS, is a schedule III controlled substance in the United States under the Controlled Substances Act.