TB-500 dosage is the most searched question about this peptide, and the hardest one to answer honestly. No human dose has ever been established, because the fragment has never been through a human pharmacokinetic study.
So the search results fill that gap with confident numbers. This page shows where those figures come from, what the research actually used, and why you cannot convert one into the other.
The short answer
- No human dose exists. TB-500 has no published pharmacokinetics, and no trial has tested a dose in people.
- Animal studies dosed by body weight. Researchers gave rodents milligrams per kilogram, on routes that varied between studies.
- You cannot scale that to yourself. Body weight arithmetic is a starting point for drug developers, not a dose for anyone.
- Every TB-500 dosage you read online is an invention. Some are careful inventions. None were measured in humans.
That is the state of the field. What follows is how to tell a serious figure from a made-up one.
Why no TB-500 dosage has been established
A dose is not a number someone liked. It comes out of a sequence.
First, researchers have to measure how the drug behaves in humans. How fast the body absorbs it. How long it stays. What the liver and kidneys do to it. None of that exists for TB-500.
Then a trial compares several doses against a placebo, so you learn the smallest amount that works and the amount where side effects begin. TB-500 has never had that stage either.
Because both steps are missing, a figure stays a guess. It may be a sensible guess, but it is not an established dose, and no article can turn it into one.
The three ways people invent a number
| Method | What it produces | Why it is not a human dose |
|---|---|---|
| Copying a forum figure | A number that repeats until readers treat it as established | Nobody can trace it to a study, because its source is usually another forum |
| Scaling a rodent mg/kg by body weight | A larger number for a larger body | It ignores how differently rodents and people process drugs |
| Allometric scaling | A figure adjusted for body surface area | A real method that regulators use to pick a cautious first dose, not a dose to use |
The third method is the most respectable of the three.
However, it is also the one people misuse most. It needs a starting point from animal data, plus a safety margin, and neither exists for a product with no human data.
What the animal studies used
Published preclinical work reports doses per kilogram of body weight. Those figures differ from one study to the next, and so do the routes.
That variation matters, because three rodent studies with three different doses leave no single animal dose to point at. What exists is a range that a researcher chose, in a species that is not you.
The endpoints differ too. Therefore tendon strength in a rat does not tell you about a return to sport, and a healed wound in a mouse does not describe a repaired shoulder.
What a real dose needs
- Human pharmacokinetics. How the body absorbs, distributes and clears the drug.
- A dose-ranging trial. Several doses against a placebo, with a defined endpoint.
- A safety margin. The distance between the effective dose and the harmful one.
- An approval or a licence. A regulator accepting all of the above for a stated use.
TB-500 has none of those four. Our guide to TB-500 covers the evidence side in more depth.
What a label can and cannot tell you
| Item | Can a label settle it? | What to look for |
|---|---|---|
| What the molecule is | Yes | A seven amino acid sequence, or a mass consistent with a heptapeptide |
| Purity | Yes | A percentage, plus the method used to measure it |
| Which batch you hold | Yes | A batch number that matches the certificate of analysis |
| The right dose | No | No label can supply this without human data |
If a certificate reports the mass of the full 43 amino acid protein while the label says TB-500, it describes a different product.
Is it the same as thymosin beta-4?
No, and that distinction decides how you read any dosage claim you find.
Thymosin beta-4 is a 43 amino acid protein. TB-500 is a seven amino acid fragment of it, Ac-LKKTETQ. Human trial data belongs to the protein, and even there the results were mixed.
So a page that quotes a protein trial to justify a TB-500 dosage describes a different molecule. In practice, that is the most common error in this niche.
What to do with a TB-500 dosage you were given
- Ask where it came from. A study, a forum, or a shop page.
- Check the species. Rodent data is not human data.
- Check the molecule. Protein or fragment, they are not interchangeable.
- Check what was measured. A lab marker is not a healed injury.
- Treat a precise figure with suspicion. Precision without data is marketing.
Storage and handling are the one part you can get right without guessing. Our guides on reconstitution and how long a mixed vial lasts cover both.
FAQ
What is the standard TB-500 dosage?
There is none. No human pharmacokinetic study and no dose-ranging trial exists, so nobody has established a dose for people.
Can I convert a rat dose to a human dose by body weight?
No. Weight alone ignores differences in metabolism, clearance and receptor behaviour, so the arithmetic produces a figure rather than a dose.
Where do the TB-500 dose figures online come from?
Mostly from other pages. Because a figure gets repeated until it reads as established, the trail usually ends at a forum post or a shop.
Does TB-500 have a half-life I can use?
Nobody has published a human figure. Our half-life chart lists TB-500 as not established for that reason.
Is TB-500 the same as thymosin beta-4 for dosing purposes?
No. They are different molecules, and data on the full protein does not transfer to the fragment.
What can a certificate of analysis tell me?
Identity, purity and batch matching. It cannot tell you a dose, because no dose exists to check it against.
Why do so many pages give exact microgram numbers?
Because precision reads as expertise. Yet a number with no study behind it is a formatting choice, not evidence.
Is TB-500 approved anywhere?
No. Neither the FDA, the EMA nor the MHRA has approved it, and WADA lists thymosin beta-4 and its derivatives including TB-500 in its S2 class.
The bottom line
A TB-500 dosage you found online is a claim, not a measurement. Treat it as you would any other claim, and ask what sits behind it.
Because no human data exists, the honest answer stays the same. Nobody knows the right dose for a person, and anyone who states one precisely is guessing in public.
Last reviewed: October 2026 by Julian Hart.
This page is educational and is not medical advice. It deliberately gives no dosing information. TB-500 is unapproved for human use, and anything involving dosing or a health condition belongs with a qualified clinician.
Sources
- McGuire FP, et al. Thymosin beta-4 and TB-500 in tissue healing, regeneration and musculoskeletal research: a scoping review. 2026.
- FDA. Estimating the maximum safe starting dose in initial clinical trials for therapeutics in adult healthy volunteers. 2005.
- FDA. Certain bulk drug substances for use in compounding that may present significant safety risks, listing the thymosin beta-4 fragment (LKKTETQ).
- WADA. The Prohibited List, S2 peptide hormones, naming thymosin-β4 and its derivatives including TB-500.
- Sosne G, et al. RGN-259 (thymosin beta-4) ophthalmic solution in neurotrophic keratopathy. 2022.
- Xing Y, et al. Progress on the function and application of thymosin beta-4. 2021.
