Trenbolone acetate, sold under brand names such as Finajet and Finaplix among others, is an androgen and anabolic steroid (AAS) medication used in veterinary medicine, specifically to increase the profitability of livestock by promoting muscle growth in cattle.

[5][10][11] In addition to its veterinary use, trenbolone acetate is used to improve physique and performance, for which purpose it is purchased from black market suppliers.

Unlike exogenous testosterone, trenbolone acetate does not cause fluid retention,[10] so bodybuilders appear leaner; therefore, it is more commonly used during preparation for competitive events.

[5][13] Trenbolone hexahydrobenzylcarbonate was previously produced for human use by Negma Pharmaceuticals of France in 1.5 ml ampoules containing 76.2 mg of the steroid.

[7][14][15] Its strong androgenic properties stimulate virilization,[7] making it unsuitable for women pursuing physique or performance enhancement.

[5] Trenbolone acetate contributes greatly to development of muscle mass and feed efficiency; however, administration of any AAS suppresses natural testosterone production and therefore has the potential to cause hypogonadism.

[21] When compared to oral AAS, trenbolone acetate exerts a stronger negative effect on cholesterol levels.

[5] However, due to trenbolone's potent progestogenic activity (it binds with high affinity to the progesterone receptor),[10][18] gynecomastia, characterized by development and swelling of breast tissue,[26] may occur.

[30][31] Trenbolone is an agonist of the progesterone receptor (PR), and in relation to this, has moderate to strong progestogenic activity.

[32][33] This naturally produced protein-based hormone affects every cell in the body of an organism and plays a large role in muscle recovery and rejuvenation.

[citation needed] The properties of glucocorticoid are the opposite of androgens as muscle tissue depletion and fat gain is promoted.

Food is one of the most anabolic substances that any living organism can consume, and therefore with the administration of trenbolone acetate, every nutrient in the body becomes a lot more valuable.

The position of these carbons slows its metabolism, which greatly increases its binding affinity to the AR, and inhibits it from undergoing aromatization into the corresponding estrogenic metabolite.

Trenbolone acetate was first synthesized in 1963 and approved by the livestock industry as a growth promoter for beef cattle in the early 1970s.

The original manufacturer of trenbolone acetate discontinued during the late 1980s and administered the synthesis of subcutaneous pellets called Finaplix.

[10] This decision was based upon the public concern of sports doping and its negative effects on athletes.

[3][4][36][37] Trenbolone acetate is or has been sold alone for veterinary use under the brand names Component TH, Component TS, Finaject, Finajet, Finaplix-H, and Finaplix-S.[3][4][5][36][37] It is or has also been sold in combination with estradiol or estradiol benzoate for veterinary use under the brand names Revalor and Synovex.

[3][4][5][36][37] Trenbolone acetate, specifically referred to as Finaplix in the livestock industry, is available to purchase in veterinary drug markets.

Major sporting and bodybuilding organizations ban the use of controlled AAS, and the possession or sale of drugs can lead to arrest and conviction of drug-trafficking in many countries, including the United States and Australia.