trenbolone

Trenbolone is a cattle implant used to make beef cattle grow faster. No human trial has ever been run on it, and the only published human reports are psychiatric emergencies, so there is no evidence base supporting human use at all.

regulatory status

US veterinary growth-promotant implant only (cattle, sheep); never approved for human use; DEA Schedule III

FDA lists trenbolone acetate among the steroid hormone implants approved for growth in food-producing animals, approved for beef cattle and sheep and explicitly not approved for dairy cows, veal calves, pigs or poultry. Trenbolone has never been approved for human use in the United States; a different ester, trenbolone hexahydrobenzylcarbonate (Parabolan), had brief human marketing in the 1980s before discontinuation in 1997. Trenbolone is named individually in the DEA schedules as 17-beta-hydroxyestr-4,9,11-trien-3-one under Schedule III, and is a Class C drug in the UK. Prohibited in sport.

The composition of the cited literature by study type. This describes the shape of the evidence, not its quality — and it does not by itself set the grade.

documented safety signals

• Acute psychiatric decompensation: published case reports document acute psychosis and steroid-induced delirium with persecutory delusions, labile affect, flight of ideas, aggression and destructive impulses requiring antipsychotic treatment.
• Aggression: trenbolone dose was significantly associated with higher verbal aggression in a survey of 282 male AAS users (p=0.045), a finding that survived compound-specific analysis where other AAS did not.
• Severe lipid derangement is the consistent clinical description for non-aromatisable high-potency androgens; class observational data show HDL-C falling from 1.08 to 0.43 mmol/l during self-administered AAS use with HDL2-C falling from 0.21 to 0.05 mmol/l (Hartgens 2004).
• Complete absence of aromatisation removes the oestrogen-mediated cardioprotective and bone-protective signalling that partially offsets androgen exposure with testosterone.
• Profound HPG-axis suppression: the case report above documented testicular atrophy with a subnormal plasma testosterone of 9.59 nmol/l during use; class data show 27.2% of former users below the lower testosterone reference limit a mean 2.5 years after cessation (Rasmussen 2016).
• Progestogenic activity, associated in the clinical literature with sexual dysfunction and prolactin-related effects, compounding the androgenic suppression.
• Cardiomyopathy and accelerated coronary atherosclerosis documented in long-term AAS users, with reduced systolic and diastolic left ventricular function (Baggish 2017).
• Polycythaemia and raised haematocrit as a general androgen class effect.
• Nephrotoxicity and renal effects have been raised in the case literature and reviews of AAS harm, though not established for trenbolone specifically in controlled work.
• There is no human product, no human labelling and no human adverse-event reporting system, so no dose-response or contraindication information exists at all; any material circulating for human use is by definition unregulated, and product-testing data in AAS cohorts found only 47% of samples contained the labelled substance (HAARLEM).
• Injection-related infection risk: 42% of 366 men injecting image- and performance-enhancing drugs reported injection-site redness, swelling and tenderness and 6.8% an abscess or open wound (Hope 2015); conversion of veterinary implant pellets into injectable preparations introduces additional sterility and identity hazards documented in harm-reduction literature.