Sustanon 250
1 year ago

Sustanon 250

Sustanon® 250 is an oil-based injectable testosterone blend that contains four different testosterone esters: testosterone propionate (30 mg); testosterone phenylpropionate (60 mg); testosterone isocaproate (60 mg); and testosterone decanoate (100 mg). Sustanon® is designed to provide a fast yet extended release of testosterone, usually requiring injections once every 3 to 4 weeks in a clinical setting. This is an improvement from standard testosterones such as cypionate or enanthate, which provide a shorter duration of activity. As with all testosterone products, Sustanon® 250 is a very strong anabolic drug with pronounced androgenic activity. It is most commonly used in bulking cycles, providing exceptional gains in strength and muscle mass. A shorteracting version of Sustanon®, called Sustanon® 100, is also made in certain areas.


Sustanon® 250 first appeared on international drug markets during the early 1970’s. It was developed by the international pharmaceutical giant Organon (now Merck/MSD), also responsible for such steroids as Durabolin®, Deca-Durabolin®, and Andriol®. Sustanon® 250 was designed to offer a therapeutic advantage over existing single esters of testosterone, which need to be injected more frequently (cited advantages in hormone stability are probably not valid). In spite of this advantage, however, Sustanon® 250 has never been approved for sale in the United States, although around the world it is one of the most popular brands of testosterone available. The lack of U.S. availability is probably due to the high costs associated with the FDA approval process and the availability of other somewhat comparable agents. Over the past 25 years, Sustanon® 250 has probably been the most sought-after injectable testosterone among athletes. It must be emphasized, however, that this is not due to an unusual potency of this testosterone combination (esters really only affect the release of testosterone).

Structural Characteristics:

Sustanon® 250 contains a mixture of four testosterone compounds, which where modified with the addition of carboxylic acid esters (propionic, propionic phenyl ester, isocaproic, and decanoic acids) at the 17-beta hydroxyl group. Esterified forms of testosterone are less polar than free testosterone, and are absorbed more slowly from the area of injection. Once in the bloodstream, the ester is removed to yield free (active) testosterone. Esterified forms of testosterone 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. Sustanon 250 is designed to provide a rapid peak in testosterone levels (24-48 hours after injection), and maintain physiological concentrations for approximately 21 days. Each 250 mg ampule provides 176mg of testosterone.

Side Effects (Estrogenic):

Testosterone is readily aromatized in the body to estradiol (estrogen). The aromatase (estrogen synthetase) enzyme is responsible for this metabolism of testosterone. Elevated estrogen levels can cause side effects such as increased water retention, body fat gain, and gynecomastia. Testosterone is considered a moderately estrogenic steroid. An anti-estrogen such as clomiphene citrate or tamoxifen citrate may be necessary to prevent estrogenic side effects. One may alternately use an aromatase inhibitor like Arimidex® (anastrozole), which more efficiently controls estrogen by preventing its synthesis. Aromatase inhibitors can be quite expensive in comparison to anti-estrogens, however, and may also have negative effects on blood lipids.
Estrogenic side effects will occur in a dose-dependant manner, with higher doses (above normal therapeutic levels) of Sustanon® 250 more likely to require the concurrent use of an anti-estrogen or aromatase inhibitor. Since water retention and loss of muscle definition are common with higher doses of testosterone, this drug is usually considered a poor choice for dieting or cutting phases of training. Its moderate estrogenicity makes it more ideal for bulking phases, where the added water retention will support raw strength and muscle size, and help foster a stronger anabolic environment.

Side Effects (Androgenic):

Testosterone is the primary male androgen, responsible for maintaining secondary male sexual characteristics. Elevated levels of testosterone are likely to produce androgenic side effects including oily skin, acne, and body/facial hair growth. Men with a genetic predisposition for hair loss (androgenetic alopecia) may notice accelerated male pattern balding. Those concerned about hair loss may find a more comfortable option in nandrolone decanoate, which is a comparably less androgenic steroid. Women are warned of the potential virilizing effects of anabolic/androgenic steroids, especially with a strong androgen such as testosterone. These may include deepening of the voice, menstrual irregularities, changes in skin texture, facial hair growth, and clitoral enlargement. In androgen-responsive target tissues such as the skin, scalp, and prostate, the high relative androgenicity of testosterone is dependant on its reduction to dihydrotestosterone (DHT). The 5-alpha reductase enzyme is responsible for this metabolism of testosterone. The concurrent use of a 5-alpha reductase inhibitor such as finasteride or dutasteride will interfere with site-specific potentiation of testosterone action, lowering the tendency of testosterone drugs to produce androgenic side effects. It is important to remember that anabolic and androgenic effects are both mediated via the cytosolic androgen receptor. Complete separation of testosterone’s anabolic and androgenic properties is not possible, even with total 5-alpha reductase inhibition.

Side Effects (Hepatotoxicity):

Testosterone does not have hepatotoxic effects; liver toxicity is unlikely. One study examined the potential for hepatotoxicity with high doses of testosterone by administering 400 mg of the hormone per day (2, mg per week) to a group of male subjects. The steroid was taken orally so that higher peak concentrations would be reached in hepatic tissues compared to intramuscular injections. The hormone was given daily for 20 days, and produced no significant changes in liver enzyme values including serum albumin, bilirubin, alanine-amino-transferase, and alkaline phosphatases.


•    17b-hydroxy-4-androsten-3-one
•    Testosterone base + 4 different esters
•    Propionate , Phenylpropionate, Isocaproate, Decanoate
•    Formula (base): C27 H40 O3
•    Molecular Weight (base): 288.429
•    Molecular Weight, Esters:
•    Propionate: 362.5082
•    Phenylpropionate: 438.6058
•    Isocaproate: 404.5886
•    Decanoate: 460.6958
•    Formula (base): C19 H28 O2
•    Melting Point (base): 155
•    Manufacturer: Organon
•    Effective Dose (Men): 500-2000mg/ week
•    Effective Dose (Women): Not recommended
•    Active life: Up to 3 weeks
•    Detection Time: 3+ months
•    Anabolic/Androgenic ratio:100/100