Boldenone acetate is boldenone with a short, two-carbon acetate ester attached at the 17β position. Boldenone itself is an anabolic-androgenic steroid (AAS) that differs from testosterone by one extra double bond in the A-ring. The acetate is a shorter-acting relative of boldenone undecylenate, the ester sold for horses as Equipoise.
The most important fact about boldenone acetate is how little is known. It is not an approved medicine for people or animals in the US, and no published study has measured its effects or kinetics in humans. The only boldenone product in the US federal animal-drug regulations is the undecylenate ester, for horses (21 CFR 522.204). What can be said about the acetate comes from its chemistry, from general rules for steroid esters, and from human data on boldenone itself.
This page summarizes what chemistry databases, regulators and the limited boldenone research report. It is for education only and is not medical advice.
| Property | Detail |
|---|---|
| Drug class | Injectable anabolic-androgenic steroid; 17β-acetate ester of boldenone |
| Chemical name | 17β-acetoxyandrosta-1,4-dien-3-one (CAS 2363-59-9) |
| Formula and weight | C₂₁H₂₈O₃, 328.4 g/mol |
| Boldenone content | About 87% of the ester’s weight |
| Approval | None for humans or animals in the US; the only US-approved boldenone product is the undecylenate, for horses |
| Doses | No approved or trial-tested dose in humans |
| Half-life | Never measured in humans or animals; short esters are expected to release faster than long ones |
| US schedule | Controlled substance, Schedule III (boldenone, including its esters) |
| WADA status | Prohibited at all times (S1.1 anabolic agents), non-specified |
What it is
Boldenone’s chemical name is 17β-hydroxyandrost-1,4-diene-3-one (21 CFR 1308.13). Boldenone acetate is the same molecule with acetic acid attached to the 17β-hydroxyl group. PubChem lists it as “1-dehydrotestosterone acetate” and “boldenone 17-acetate,” with formula C₂₁H₂₈O₃ and molecular weight 328.4 g/mol (PubChem: boldenone acetate). Boldenone itself weighs 286.4 g/mol (PubChem: boldenone).
The structure of boldenone, its relationship to testosterone, methandienone (Dianabol) and dihydroboldenone, and its small natural occurrence in the body are covered on the Equipoise page. This page focuses on what the acetate ester changes.
How the ester changes the drug
An ester has no hormonal activity of its own. Injectable steroids are usually esterified at the 17β-hydroxyl group to slow absorption from the oil vehicle; once in the circulation, blood esterases cleave the ester and release the active steroid (Kicman, Br J Pharmacol 2008). Kicman notes that the duration of action depends on absorption from the injection site, and that, “in general,” longer ester chains are released more slowly.
The boldenone esters in this library compare as follows. The extra carbons and boldenone share are calculated from the PubChem formulas and weights (PubChem: acetate; cypionate; undecylenate):
| Form | Formula | Molecular weight | Carbons added by ester | Boldenone share by weight |
|---|---|---|---|---|
| Boldenone (free steroid) | C₁₉H₂₆O₂ | 286.4 g/mol | 0 | 100% |
| Boldenone acetate | C₂₁H₂₈O₃ | 328.4 g/mol | 2 | ≈ 87% |
| Boldenone cypionate | C₂₇H₃₈O₃ | 410.6 g/mol | 8 | ≈ 70% |
| Boldenone undecylenate (Equipoise) | C₃₀H₄₄O₃ | 452.7 g/mol | 11 | ≈ 63% |
Two practical points follow:
- More boldenone per milligram. Because the acetate group is small, about 87 of every 100 mg of the ester is boldenone, compared with about 63 mg for the undecylenate.
- Expected faster release. By the general chain-length rule, the acetate should leave an oil depot faster than the cypionate or undecylenate. This is an inference from steroid-ester pharmacology. It has not been measured for boldenone acetate.
About the half-life. Online sources often quote a half-life for boldenone acetate. We found no pharmacokinetic study of boldenone acetate in people or animals, so we do not give a number here. The only measured boldenone kinetics are for the undecylenate in horses, described on the Equipoise page.
How boldenone behaves in the body
Once the acetate is cleaved, the drug in the blood is ordinary boldenone, the same as from any other ester. The human data on boldenone itself are limited to drug-testing studies:
- Metabolism. Three men and three women each took a single 30 mg oral dose of boldenone (not an ester). Boldenone, its metabolite 5β-androst-1-en-17β-ol-3-one (BM1) and its 17α-epimer were excreted in urine. In most volunteers, BM1 levels were higher than boldenone’s, and metabolic patterns did not differ between men and women (Wu et al., J Pharm Biomed Anal 2015).
- Natural background. The same study found low concentrations of boldenone, BM1 and 17α-boldenone in urine naturally. When boldenone is found at low levels in an athlete’s urine, isotope-ratio mass spectrometry (a test that tells synthetic from body-made steroids by their carbon signature) may be needed to confirm an outside source (Gómez et al., J Steroid Biochem Mol Biol 2012).
- Detecting the ester itself. Finding an intact steroid ester in blood is considered unequivocal evidence that the steroid was given from outside. Anti-doping labs have developed dried-blood-spot methods that detect testosterone, nandrolone and boldenone esters directly (Sakellariou et al., Drug Test Anal 2026).
How much boldenone converts to estrogen in people, how strongly it binds the androgen receptor compared with testosterone, and how it suppresses natural testosterone production have not been measured in human studies.
Regulatory status
- No approved product. We found no boldenone acetate product in FDA’s drug databases. The federal regulation for boldenone as an animal drug specifies only boldenone undecylenate, 25 or 50 mg/mL, for debilitated horses (21 CFR 522.204). Kicman’s review describes boldenone as restricted to veterinary use in some countries (Kicman 2008).
- US controlled substance. Boldenone is a named Schedule III anabolic steroid, and the listing covers “its salts, esters and ethers,” so boldenone acetate is also Schedule III (21 CFR 1308.13).
- Sport. The 2026 WADA Prohibited List names boldenone under S1.1 anabolic androgenic steroids, together with “other substances with a similar chemical structure or similar biological effect(s) including their esters.” S1 substances are prohibited in and out of competition and are non-specified (WADA 2026 Prohibited List).
What the research shows
No randomized or controlled trial has tested boldenone acetate, or boldenone in any form, for muscle, strength, body composition or any medical condition in people. A PubMed search for boldenone acetate returns mostly analytical methods for drug testing and food-residue control, and no clinical studies.
Claims that the acetate gives “faster results,” “less water retention” or a “drier look” than other boldenone esters come from user reports. Once the ester is removed, the active drug is the same boldenone, so any difference would be in timing, not in kind. The class effects of AAS on muscle are well documented with testosterone (see Testosterone cypionate); whether boldenone differs from testosterone in people has not been studied.
Side effects and risks
There are no boldenone acetate safety data. What is known about boldenone in humans comes from case reports involving other esters or unspecified forms, usually alongside other drugs. Risk information therefore rests mostly on AAS as a class.
Case reports involving boldenone
- Kidney markers. A 37-year-old man referred for a raised creatinine and abnormal estimated kidney function (eGFR), with no other signs of kidney disease, was found to be using boldenone. The authors linked the raised creatinine to boldenone and warned that creatinine alone can lead to a misdiagnosis of kidney disease (Winnett et al., Nephrol Dial Transplant 2011).
- Heart failure. A 39-year-old weightlifter developed fulminant heart failure with left ventricular systolic function estimated at 15%. His dilated cardiomyopathy was attributed to testosterone and boldenone use in the previous 3 months (White et al., Can J Cardiol 2018).
Single case reports cannot prove that boldenone caused these problems. More detail, including animal toxicology, is on the Equipoise page.
Class effects of anabolic steroids
The Endocrine Society’s scientific statement links performance-enhancing drug use to a higher risk of death and to cardiovascular, psychiatric, metabolic, endocrine, hepatic and renal disorders (Pope et al., Endocr Rev 2014). Among the effects it describes in AAS users:
- cardiomyopathy and lower HDL (“good”) cholesterol with higher LDL cholesterol;
- suppressed LH, FSH and natural testosterone, low sperm counts and testicular atrophy;
- higher hemoglobin and hematocrit (the share of blood made up of red cells).
Nothing shows that boldenone acetate avoids these effects. A faster-releasing ester does not make the drug milder; it changes how quickly levels rise and fall.
Who should not use it
Because boldenone acetate has no approved label, there are no official contraindications or dosing. As with all AAS, irreversible virilization (masculinizing effects) is a recognized risk in women (Kicman 2008).
Quality and contamination
Any boldenone acetate in circulation comes from outside the regulated drug supply, so its identity, dose and sterility are not checked. Analyses of seized and user-supplied products show how unreliable this market is:
| Study | Products tested | Key finding |
|---|---|---|
| Czech Republic and Slovakia (Tircova et al., Drug Test Anal 2019) | 358 AAS products from users | 58.9% matched the label; 15.9% had no active substance; 16.8% were under-dosed; 4.5% had a different substance; 3.6% were over-dosed |
| Denmark (Heinsvig et al., Drug Test Anal 2023) | 764 police-seized products | No API or the wrong API (active ingredient) in 25–34% of products |
Neither study reported boldenone acetate separately, but the findings apply to the illicit AAS market as a whole.
Key takeaways
- A short ester of boldenone. Boldenone acetate is boldenone with a two-carbon ester; about 87% of its weight is boldenone.
- No approved product and no human data. There is no US-approved human or veterinary boldenone acetate product, and no study has measured its effects or kinetics in people.
- Faster release is inferred, not measured. Shorter esters generally leave the injection site faster, but no half-life for boldenone acetate has been published.
- Same drug after cleavage. Once the ester is removed, the active steroid is ordinary boldenone, with the same class risks as other AAS.
- Controlled and banned in sport. Boldenone and its esters are Schedule III in the US and prohibited at all times by WADA.
Sources
- National Center for Biotechnology Information. Boldenone acetate, PubChem CID 102247. PubChem.
- National Center for Biotechnology Information. Boldenone, PubChem CID 13308. PubChem.
- National Center for Biotechnology Information. Boldenone cypionate, PubChem CID 71314193. PubChem.
- National Center for Biotechnology Information. Boldenone undecylenate, PubChem CID 11954310. PubChem.
- Kicman AT. Pharmacology of anabolic steroids. Br J Pharmacol. 2008;154(3):502–521. PubMed.
- 21 CFR 522.204. Boldenone. Electronic Code of Federal Regulations. eCFR.
- 21 CFR 1308.13. Schedule III. Electronic Code of Federal Regulations. eCFR.
- World Anti-Doping Agency. The 2026 Prohibited List. In effect from January 1, 2026. WADA.
- Wu X, Gao F, Zhang W, Ni J. Metabolism study of boldenone in human urine by gas chromatography-tandem mass spectrometry. J Pharm Biomed Anal. 2015;115:570–575. PubMed.
- Gómez C, Pozo OJ, Geyer H, et al. New potential markers for the detection of boldenone misuse. J Steroid Biochem Mol Biol. 2012;132(3-5):239–246. PubMed.
- Sakellariou P, Thomas A, Schröder SM, et al. Simultaneous detection of steroid esters and multi-class substances in dried blood spots by LC-HRMS/MS from a single spot for human doping control. Drug Test Anal. Published online September 21, 2026. PubMed.
- Winnett G, Cranfield L, Almond M. Apparent renal disease due to elevated creatinine levels associated with the use of boldenone. Nephrol Dial Transplant. 2011;26(2):744–747. PubMed.
- White M, Brennan E, Mi Ren KY, et al. Anabolic androgenic steroid use as a cause of fulminant heart failure. Can J Cardiol. 2018;34(10):1369.e1–1369.e3. PubMed.
- Pope HG Jr, Wood RI, Rogol A, et al. Adverse health consequences of performance-enhancing drugs: an Endocrine Society scientific statement. Endocr Rev. 2014;35(3):341–375. PubMed.
- Tircova B, Bosakova Z, Kozlik P. Development of an ultra-high performance liquid chromatography-tandem mass spectrometry method for the determination of anabolic steroids currently available on the black market in the Czech Republic and Slovakia. Drug Test Anal. 2019;11(2):355–360. PubMed.
- Heinsvig PJ, Christiansen AV, Ayoubi D, et al. Do you get what you see? The illicit doping market in Denmark: an analysis of performance and image enhancing drugs seized by the police over a 1-year period. Drug Test Anal. 2023;15(6):668–677. PubMed.