Masteron, the most recognized trade name for drostanolone propionate, is an injectable anabolic steroid derived from dihydrotestosterone (DHT). Here, the DHT backbone has been modified with a 2-methyl group to increase its anabolic properties, making this agent significantly more effective at promoting the growth of muscle tissue than its non-methylated parent. Drostanolone propionate is described in product literature as a “steroid with powerful anabolic and anti-estrogenic properties,” and indeed does seem to share some of both properties. Admittedly, however, its anabolic properties are more properly described as moderate, especially when placed in the context of other agents. The drug is most often used by dieting bodybuilders and athletes in speed sports, where it is highly favored for its ability to produce solid increases in lean muscle mass and strength, which are usually accompanied by reductions in body fat level and minimal side effects.
Drostanolone propionate was first described in 1959.1 Syntex developed the agent alongside such other well-known steroids as Anadrol and methyl drostanolone (Superdrol), also first described in the same paper. Drostanolone propionate would be introduced as a prescription drug product approximately a decade later. Lilly had an agreement with Syntex to split certain research and development costs in exchange for the rights to market the results of that research. Lilly would, therefore, sell drostanolone propionate in the U.S. under the Drolban brand name, while Syntex would sell/license it in other markets. Products included Masteron in Belgium (Sarva-Syntex) and Portugal (Cilag), Masteril in the U.K. and Bulgaria, and Metormon in Spain. Drostanolone propionate was also found in such popular preparations as Permastril (Cassenne, France), Mastisol (Shionogi, Japan), and Masterid (Grunenthal, Germany Democratic Republic).
The U.S. Food and Drug Administration approved drostanolone propionate for the treatment of advanced inoperable breast cancer in postmenopausal women. This remained the principal clinical indication for the agent in all international markets as well. The prescribing literature reminds doctors and female patients that there is considerably less virilization with drostanolone propionate as compared to equal doses of testosterone propionate, suggesting this was a much more comfortable alternative to testosterone injections for the given audience. Still, the given dosage level (300 mg per week) was relatively high, and the literature also reminds us that mild virilization symptoms still commonly occur, such as deepening of the voice, acne, facial hair growth, and enlargement of the clitoris. It also reports that marked virilization sometimes follows long-term therapy.
While highly popular among athletes during the 1970s and ’80s, drostanolone propionate ultimately enjoyed limited success as a prescription agent. Manufacturers began voluntarily discontinuing the sale of the agent in various markets before long, likely due to the advent of more effective therapies for breast cancer, as well as the slow decline in steroid prescriptions for this phase of treatment. One of the first preparations to go was the U.S. Drolban, which was removed from the market during the late 1980s. Permastril and Metormon were soon dropped as well. The last remaining Western preparation containing drostanolone propionate was Masteron from Belgium, which disappeared by the late 1990s. Drostanolone propionate remains listed on the U.S. Pharmacopias, suggesting there is presently no legal roadblock to its sale, although its reemergence as a prescription drug product seems highly unlikely.
Masteron is no longer available as a prescription drug preparation. When produced, it was supplied in the form of 1 mL and 2 mL ampules and 10 mL vials containing 50 mg/ml or 100 mg/ml of steroid in oil.
Drostanolone (also known as dromostanolone) is a modified form of dihydrotestosterone. It differs by the introduction of a methyl group at carbon-2 (alpha), which considerably increases the anabolic strength of the steroid by heightening its resistance to metabolism by the 3-hydroxysteroid dehydrogenase enzyme in skeletal muscle tissue. Drostanolone propionate is a modified form of drostanolone, where a carboxylic acid ester (propionic acid) has been attached to the 17-beta hydroxyl group. Esterified steroids are less polar than free steroids, and are absorbed more slowly from the area of injection. Once in the bloodstream, the ester is removed to yield free (active) drostanolone. Esterified steroids are designed to prolong the window of therapeutic effect following administration, allowing for a less frequent injection schedule compared to injections of free (unesterified) steroid. The half-life of drostanolone propionate is approximately two days after injection.
Side Effects (Estrogenic)
Drostanolone is not aromatized by the body and is not measurably estrogenic. An anti-estrogen is not necessary when using this steroid, as gynecomastia should not be a concern even among sensitive individuals. Since estrogen is the usual culprit with water retention, drostanolone instead produces a lean, quality look to the physique with no fear of excess subcutaneous fluid retention. This makes it a favorable steroid to use during cutting cycles when water and fat retention are major concerns. As a nonaromatizable DHT derivative, drostanolone may impart an anti-estrogenic effect, the drug competing with other (aromatizable) substrates for binding to the aromatase enzyme.
Side Effects (Androgenic)
Although classified as an anabolic steroid, androgenic side effects are still possible with this substance, especially with higher than normal therapeutic doses. This may include bouts of oily skin, acne, and body/facial hair growth. Anabolic/androgenic steroids may also aggravate male pattern hair loss. Women are warned of the potential virilizing effects of anabolic/androgenic steroids. These may include a deepening of the voice, menstrual irregularities, changes in skin texture, facial hair growth, and clitoral enlargement.
Drostanolone is a steroid with relatively low androgenic activity relative to its tissue-building actions, making the threshold for strong androgenic side effects comparably higher than with more androgenic agents such as testosterone, methandrostenolone, or fluoxymesterone. Note that drostanolone is unaffected by the 5-alpha reductase enzyme, so its relative androgenicity is not affected by the concurrent use of finasteride or dutasteride.
Side Effects (Hepatotoxicity)
Masteron is not c17-alpha alkylated, and not known to have hepatotoxic properties. Liver toxicity is unlikely.
Side Effects (Cardiovascular)
Anabolic/androgenic steroids can have deleterious effects on serum cholesterol. This includes a tendency to reduce HDL (good) cholesterol values and increase LDL (bad) cholesterol values, which may shift the HDL to LDL balance in a direction that favors greater risk of arteriosclerosis. The relative impact of an anabolic/androgenic steroid on serum lipids is dependant on the dose, route of administration (oral vs. injectable), type of steroid (aromatizable or non-aromatizable), and level of resistance to hepatic metabolism. Drostanolone should have a stronger negative effect on the hepatic management of cholesterol than testosterone or nandrolone due to its non-aromatizable nature, but a weaker impact than c-17 alpha-alkylated steroids. Anabolic/androgenic steroids may also adversely affect blood pressure and triglycerides, reduce endothelial relaxation, and support left ventricular hypertrophy, all potentially increasing the risk of cardiovascular disease and myocardial infarction.
To help reduce cardiovascular strain it is advised to maintain an active cardiovascular exercise program and minimize the intake of saturated fats, cholesterol, and simple carbohydrates at all times during active AAS administration. Supplementing with fish oils (4 grams per day) and a natural cholesterol/antioxidant formula such as Lipid Stabil or a product with comparable ingredients is also recommended.
Side Effects (Testosterone Suppression)
All anabolic/androgenic steroids, when taken in doses sufficient to promote muscle gain, are expected to suppress endogenous testosterone production. Without the intervention of testosterone-stimulating substances, testosterone levels should return to normal within 1-4 months of drug secession. Note that prolonged hypogonadotrophic hypogonadism can develop secondary to steroid abuse, necessitating medical intervention.
Drostanolone propionate was not FDA approved for use in men. Prescribing guidelines are unavailable. For physique- or performance-enhancing purposes, this drug is usually injected three times per week. The total weekly dosage is typically 200-400 mg, which is taken for 6-12 weeks. This level of use is sufficient to provide measurable gains in lean muscle mass and strength.
Drostanolone propionate is often combined with other steroids for an enhanced effect. Common stacks include an injectable anabolic such as Deca-Durabolin® (nandrolone decanoate) or Equipoise® (boldenone undecylenate), which can provide notably enhanced muscle gains without excessive water retention. For mass gains, it is often combined with an injectable testosterone. The result here can be solid muscle gain, with a lower level of water retention and other estrogenic side effects than if these steroids were used alone (usually in higher doses). Masteron, however, is most commonly applied during cutting phases of training. Here it is often combined with other non-aromatizable steroids such as Winstrol®, Primobolan®, Parabolan, or Anavar, which can greatly aid muscle retention and fat loss, during a period which can be very catabolic without steroids.
The prescribing guidelines for Drolban recommended a dose of 100 mg given three times per week. Therapy is given for a minimum of 8 to 12 weeks before an evaluation of its efficacy is made. If successful, the drug may be continued for as long as satisfactory results are obtained. Note that virilization symptoms were common at the recommended dosage. When used for physique- or performance-enhancing purposes, a dosage of 50 mg per week is most common, taken for 4 to 6 weeks. Virilization symptoms are rare in doses of 100 mg per week or below. Note that due to the short-acting nature of the propionate ester, the total weekly dosage is usually subdivided into smaller injections given once every second or third day.
Drostanolone propionate is presently unavailable as a prescription drug product. There are limited supplies from export-oritented pharmaceutical companies, but the vast majority comes from underground steroid manufacturers.