Trenbolone enanthate
1 year ago

Trenbolone enanthate


Trenbolone enanthate is an injectable form of the strong anabolic steroid trenbolone. Given the use of an enanthate ester, this drug will exhibit virtually identical pharmacokinetics to testosterone enanthate, providing a peak release of its steroid within the first several days after injection, followed by declining levels for approximately 2 weeks. The base steroid here (trenbolone) is a derivative of nandrolone, and exhibits strong anabolic and androgenic properties. On a milligram for milligram basis it is considerably more potent than testosterone as both an anabolic and androgenic agent, though it does carry a more favorable balance (toward anabolism). Trenbolone is also unable to convert to estrogen, however it does exhibit notable progestational activity, which may mimic estrogenic side effects given the right physiological conditions. Trenbolone enanthate is virtually interchangeable with Parabolan (trenbolone hexahydrobenzylcarbonate), capable of promoting strong gains in lean muscle mass, often with an accompanying increase in relative hardness and definition.


Slow-acting trenbolone esters were first studied in 1967, during a series of experiments into synthetic anabolic steroids by Roussel-UCLAF. Roussel did not specifically investigate Trenbolone enanthate, although the drug would have remained an obvious possibility once trenbolone was released given the widespread application of steroid esters (including enanthate) by the 1960’s. The drug would not see the light of day for many decades, however, and was only first released for commercial sale in 2004. It was introduced by British Dragon, an underground manufacturer. British Dragon would sell it under the trade name Trenabol, in 200 mg/mL strength.

Although it was not for sale through pharmacies nor approved for human or veterinary use, Trenabol was widely distributed throughout the world, and became an extremely popular product with athletes and bodybuilders.

Structural Characteristics:

Trenbolone is a modified form of nandrolone. It differs by the introduction of double bonds at carbons 9 and 11, which inhibit aromatization (9-ene), increase androgen-binding affinity, and slows its metabolism. The resulting steroid is significantly more potent as both an anabolic and an androgen than its nandrolone base. The trenbolone here is modified with an enanthate ester at the 17-beta hydroxyl group, so that the free steroid is released more slowly from the area of injection.

Side Effects (Estrogenic):

Trenbolone is not aromatized by the body, and is not measurably estrogenic. It is of note, however, that this steroid displays significant binding affinity for the progesterone receptor (slightly stronger than progesterone itself ).  The side effects associated with progesterone are similar to those of estrogen, including negative feedback inhibition of testosterone production and enhanced rate of fat storage.

Progestins also augment the stimulatory effect of estrogens on mammary tissue growth. There appears to be a strong synergy between these two hormones, such that gynecomastia might even occur with the help of progestins, without excessive estrogen levels. The use of an antiestrogen, which inhibits the estrogenic component of this disorder, is often sufficient to mitigate gynecomastia caused by progestational anabolic/androgenic steroids. Note that progestational side effects are more common when trenbolone is being taken with other aromatizable steroids.

Side Effects (Androgenic):

Although classified as an anabolic steroid, trenbolone is sufficiently androgenic. Androgenic side effects are still common with this substance, and may include bouts of oily skin, acne, and body/facial hair growth. Anabolic/androgenic steroids may also aggravate male pattern hair loss. Women are also 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. Additionally, the 5-alpha reductase enzyme does not metabolize trenbolone, so its relative androgenicity is not affected by finasteride or dutasteride.

Side Effects (Hepatotoxicity):

Trenbolone is not c-17 alpha alkylated, and is generally not considered a hepatotoxic steroid; liver toxicity is unlikely. This steroid does have a strong level of resistance to hepatic breakdown, however, and severe liver toxicity has been noted in bodybuilders abusing trenbolone. Although unlikely, hepatotoxicity cannot be completely excluded, especially with high doses.


• 17b-hydroxy-4-androsten-3-one
• Testosterone base + Enanthate ester
• Molecular Weight: 412.6112
• Molecular Weight (base): 288.429
• Molecular Weight (ester): 130.1864
• Formula (base): C19 H28 O2
• Formula (ester):C7 H12 O
• Melting Point (base): 155
• Manufacturer: Various
• Effective Dose (Men): 300-2000mg+ week
• Effective Dose (Women): Not recommended
• Active life: 10.5 days
• Detection Time: 3 months
• Anabolic/Androgenic ratio:100/100