Boldenone
Human data are limited to urinary metabolism in six volunteers after oral free boldenone. The 123-hour half-life comes from horses; no controlled human trial establishes muscle gain or a safe injectable regimen.
Anabolic-androgenic steroid
- Equipoise / undecylenate
- Veterinary authorization
What is boldenone, also called Equipoise?
Boldenone is an anabolic-androgenic steroid. The cited US veterinary medicine contains the undecylenate ester for use in horses.
A long-chain ester changes release from an injection depot. The oral free drug used in human metabolism research is not the same preparation. A veterinary authorization does not authorize human use.
US regulation · horse use
Veterinary regulation
21 CFR 522.204.
The regulation covers boldenone undecylenate for debilitated horses when improved weight, coat or general condition is desired. It restricts use to veterinary supervision and excludes horses intended for human consumption.
Read the original sourceChinese human study · urinary metabolism
Human analytical metabolism study
Journal of pharmaceutical and biomedical analysis. PMID 26319750.
Three men and three women received oral free boldenone. Investigators measured urinary parent drug and metabolites, including conjugated forms.
The study examined excretion and doping analysis, not muscle gain, cardiovascular safety or the plasma half-life of injectable undecylenate.
Read the original sourceHas boldenone been studied in people?
A six-volunteer experiment measured urinary metabolism after oral free boldenone. It did not test muscle gain, fat loss, performance, or injected undecylenate.
A Chinese research group studied urine from three male and three female volunteers after oral free boldenone. It identified how the drug and metabolites were excreted. It did not evaluate a bodybuilding result or an injected undecylenate regimen.
Chinese human study · urinary metabolism
Human analytical metabolism study
Journal of pharmaceutical and biomedical analysis. PMID 26319750.
Three men and three women received oral free boldenone. Investigators measured urinary parent drug and metabolites, including conjugated forms.
The study examined excretion and doping analysis, not muscle gain, cardiovascular safety or the plasma half-life of injectable undecylenate.
Read the original sourceDoes veterinary weight gain establish a human benefit?
No. The veterinary indication concerns debilitated horses. It cannot supply an expected human lean-mass gain, appetite effect, endurance improvement or safe amount.
US regulation · horse use
Veterinary regulation
21 CFR 522.204.
The regulation covers boldenone undecylenate for debilitated horses when improved weight, coat or general condition is desired. It restricts use to veterinary supervision and excludes horses intended for human consumption.
Read the original sourceHuman evidence · unresolved questions
Evidence summary
Primary indexed and product records.
The cited sources include horse regulation, equine pharmacokinetics, rat toxicology and a Chinese human urinary-metabolism study. They do not establish a controlled human muscle-gain benefit, a validated human injection half-life or a current approved human product.
Is boldenone a mild or safer steroid?
No comparative human study establishes boldenone as milder or safer than other anabolic steroids.
Relevant anabolic-steroid concerns include cardiovascular and cholesterol changes, androgenic effects, mood changes and reproductive suppression. The exact frequency and severity under boldenone use cannot be calculated from horse studies or a six-person metabolism experiment.
FDA · steroid-product risks
Regulatory safety review
US FDA, 2017.
Anabolic-steroid products have been associated with serious liver and cardiovascular injury, mood changes, adverse lipids, androgenic effects and reproductive suppression.
This describes class-level concerns. It does not estimate a specific compound’s risk.
Read the original sourceChinese human study · urinary metabolism
Human analytical metabolism study
Journal of pharmaceutical and biomedical analysis. PMID 26319750.
Three men and three women received oral free boldenone. Investigators measured urinary parent drug and metabolites, including conjugated forms.
The study examined excretion and doping analysis, not muscle gain, cardiovascular safety or the plasma half-life of injectable undecylenate.
Read the original sourceHuman evidence · unresolved questions
Evidence summary
Primary indexed and product records.
The cited sources include horse regulation, equine pharmacokinetics, rat toxicology and a Chinese human urinary-metabolism study. They do not establish a controlled human muscle-gain benefit, a validated human injection half-life or a current approved human product.
Does it raise red blood cells more than other steroids?
No reliable human study quantifies a larger hematocrit effect than other anabolic steroids. An elevated hematocrit needs clinical evaluation; the cited studies do not validate a self-directed donation schedule.
Human evidence · unresolved questions
Evidence summary
Primary indexed and product records.
The cited sources include horse regulation, equine pharmacokinetics, rat toxicology and a Chinese human urinary-metabolism study. They do not establish a controlled human muscle-gain benefit, a validated human injection half-life or a current approved human product.
FDA · steroid-product risks
Regulatory safety review
US FDA, 2017.
Anabolic-steroid products have been associated with serious liver and cardiovascular injury, mood changes, adverse lipids, androgenic effects and reproductive suppression.
This describes class-level concerns. It does not estimate a specific compound’s risk.
Read the original sourceDoes a non-17-alpha-alkylated formulation remove all organ risk?
No. The absence of one structural feature does not establish cardiovascular, endocrine or overall safety. A compound can lack the characteristic oral-steroid modification and still expose other tissues to androgen effects.
FDA · steroid-product risks
Regulatory safety review
US FDA, 2017.
Anabolic-steroid products have been associated with serious liver and cardiovascular injury, mood changes, adverse lipids, androgenic effects and reproductive suppression.
This describes class-level concerns. It does not estimate a specific compound’s risk.
Read the original sourceHuman evidence · unresolved questions
Evidence summary
Primary indexed and product records.
The cited sources include horse regulation, equine pharmacokinetics, rat toxicology and a Chinese human urinary-metabolism study. They do not establish a controlled human muscle-gain benefit, a validated human injection half-life or a current approved human product.
What does the reproductive study show?
The direct toxicology study is in rats: sperm count and motility fell, with hormone and testicular changes after repeated boldenone-undecylenate exposure.
That is a hazard signal, not a percentage risk for a person. Vitamin C partly improved some measurements but did not restore all hormone or receptor findings. The study does not validate a supplement-based protection plan.
Reproductive toxicity · male rats
Animal experiment
Antioxidants (Basel, Switzerland). PMID 33126548.
Eight-week boldenone-undecylenate exposure in male rats reduced sperm count and motility and disrupted reproductive hormones and testicular measures. Vitamin C did not reverse all hormone or receptor changes.
This identifies a reproductive hazard in rats. It does not supply a human infertility rate or prove a protective supplement regimen.
Read the original sourceWhy does the formulation matter so much?
A depot ester, the free drug in blood and metabolites in urine are different stages of exposure. Each requires its own measurement.
An orally administered free-parent study can answer metabolism questions while leaving injection release and clearance unresolved. The horse study measured plasma concentrations after an intramuscular preparation, but changing species prevents a direct human extrapolation.
Chinese human study · urinary metabolism
Human analytical metabolism study
Journal of pharmaceutical and biomedical analysis. PMID 26319750.
Three men and three women received oral free boldenone. Investigators measured urinary parent drug and metabolites, including conjugated forms.
The study examined excretion and doping analysis, not muscle gain, cardiovascular safety or the plasma half-life of injectable undecylenate.
Read the original sourceHorse pharmacokinetics · 123 hours
Animal pharmacokinetic study
Journal of veterinary pharmacology and therapeutics. PMID 17348894.
The horse study reported a median elimination half-life of 123 hours for intramuscular boldenone, with an absorption half-life of 8.5 hours.
These values describe an equine preparation and cannot be assigned to humans.
Read the original sourceIs 123 hours a valid human boldenone half-life?
No. 123 hours is a horse-study result. The six-person human study measured urine, not terminal plasma elimination of an injected ester.
Neither source establishes how long an underground human injection remains active or how long effects and adverse effects take to resolve. A metabolite detection window is also not the same as ongoing clinical activity.
Horse pharmacokinetics · 123 hours
Animal pharmacokinetic study
Journal of veterinary pharmacology and therapeutics. PMID 17348894.
The horse study reported a median elimination half-life of 123 hours for intramuscular boldenone, with an absorption half-life of 8.5 hours.
These values describe an equine preparation and cannot be assigned to humans.
Read the original sourceChinese human study · urinary metabolism
Human analytical metabolism study
Journal of pharmaceutical and biomedical analysis. PMID 26319750.
Three men and three women received oral free boldenone. Investigators measured urinary parent drug and metabolites, including conjugated forms.
The study examined excretion and doping analysis, not muscle gain, cardiovascular safety or the plasma half-life of injectable undecylenate.
Read the original sourceHuman evidence · unresolved questions
Evidence summary
Primary indexed and product records.
The cited sources include horse regulation, equine pharmacokinetics, rat toxicology and a Chinese human urinary-metabolism study. They do not establish a controlled human muscle-gain benefit, a validated human injection half-life or a current approved human product.
What does the approved veterinary product tell us about an online vial?
It establishes the identity and conditions of a specific veterinary medicine. It does not verify another product’s ingredient, concentration or suitability for people.
U.S. FDA records contain no current approved human boldenone product. Veterinary manufacturing standards do not establish human clinical safety.
US regulation · horse use
Veterinary regulation
21 CFR 522.204.
The regulation covers boldenone undecylenate for debilitated horses when improved weight, coat or general condition is desired. It restricts use to veterinary supervision and excludes horses intended for human consumption.
Read the original sourceHuman evidence · unresolved questions
Evidence summary
Primary indexed and product records.
The cited sources include horse regulation, equine pharmacokinetics, rat toxicology and a Chinese human urinary-metabolism study. They do not establish a controlled human muscle-gain benefit, a validated human injection half-life or a current approved human product.
Studies and sources
US regulation · horse use
Veterinary regulation
21 CFR 522.204.
The regulation covers boldenone undecylenate for debilitated horses when improved weight, coat or general condition is desired. It restricts use to veterinary supervision and excludes horses intended for human consumption.
Read the original sourceHorse pharmacokinetics · 123 hours
Animal pharmacokinetic study
Journal of veterinary pharmacology and therapeutics. PMID 17348894.
The horse study reported a median elimination half-life of 123 hours for intramuscular boldenone, with an absorption half-life of 8.5 hours.
These values describe an equine preparation and cannot be assigned to humans.
Read the original sourceChinese human study · urinary metabolism
Human analytical metabolism study
Journal of pharmaceutical and biomedical analysis. PMID 26319750.
Three men and three women received oral free boldenone. Investigators measured urinary parent drug and metabolites, including conjugated forms.
The study examined excretion and doping analysis, not muscle gain, cardiovascular safety or the plasma half-life of injectable undecylenate.
Read the original sourceReproductive toxicity · male rats
Animal experiment
Antioxidants (Basel, Switzerland). PMID 33126548.
Eight-week boldenone-undecylenate exposure in male rats reduced sperm count and motility and disrupted reproductive hormones and testicular measures. Vitamin C did not reverse all hormone or receptor changes.
This identifies a reproductive hazard in rats. It does not supply a human infertility rate or prove a protective supplement regimen.
Read the original sourceFDA · steroid-product risks
Regulatory safety review
US FDA, 2017.
Anabolic-steroid products have been associated with serious liver and cardiovascular injury, mood changes, adverse lipids, androgenic effects and reproductive suppression.
This describes class-level concerns. It does not estimate a specific compound’s risk.
Read the original sourceHuman evidence · unresolved questions
Evidence summary
Primary indexed and product records.
The cited sources include horse regulation, equine pharmacokinetics, rat toxicology and a Chinese human urinary-metabolism study. They do not establish a controlled human muscle-gain benefit, a validated human injection half-life or a current approved human product.
Why is Boldenone in F tier?
F reflects no substantiated human therapeutic benefit-risk profile. Equine pharmacokinetics and rat toxicology cannot supply a human injection regimen.