TB-500 calculator
A synthetic fragment related to thymosin beta-4, discussed alongside BPC-157 in repair-focused protocols.
Also known as: Thymosin Beta-4 fragment, TB4
FDA status — not an approved drug Not FDA-approved for any use. Thymosin beta-4 was placed in Category 2 of FDA's bulk drug substances list. Prohibited in sport by WADA.
Schedule TB-500 → Set your dosing schedule and get a phone notification when each dose is due. Free.
What TB-500 is
TB-500 is a synthetic version of a fragment of thymosin beta-4, a protein involved in cell migration and wound repair. It is used almost exclusively in veterinary and research contexts, and it is banned in human and equine sport.
Research depth: 3/5 Substantial preclinical work on thymosin beta-4 in wound healing and cardiac repair; human data is limited to early-phase studies. Human trials: Early-phase only. This measures how much has been studied — counting animal and laboratory work — not whether it works for you.
How TB-500 works
Thymosin beta-4 binds actin and regulates its assembly, which affects how cells migrate into an injured area. Animal work suggests roles in blood vessel formation and reduced inflammatory scarring. Human efficacy at community-used doses is unestablished.
TB-500 side effects
Commonly reported
- Injection-site reactions
- Lethargy or head-rush sensations reported anecdotally
- No systematic human safety data
Serious — seek medical care
- Unknown. As with BPC-157, the angiogenic mechanism raises theoretical concern about promoting existing tumor growth
- Prohibited by WADA — a positive test carries sporting sanctions
This list is not exhaustive. Report anything unexpected to the clinician who prescribed it. If you have severe abdominal pain, trouble breathing, or signs of an allergic reaction, seek care the same day. See also our guide to peptide side effects by class.
A worked example
A 5 mg vial reconstituted with 2 mL of bacteriostatic water gives 2.5 mg/mL. A 2500 mcg dose is then 1 mL — about 100 units on a 100-unit insulin syringe, giving roughly 2 doses per vial before accounting for residual volume left in the vial and syringe.
Prefer paper? Download the printable TB-500 dosing chart (PDF) — every vial size and water volume in syringe units, with the same review byline as this page. All charts →
Commonly cited dose range
Figures circulating for TB-500 run from 2000 mcg to 5000 mcg. Community protocols typically describe a loading period followed by less frequent maintenance dosing. No approved human dose exists.
Read this as reference information, not instruction. These numbers describe what is commonly discussed, not what is right for any individual. Dose, frequency, and whether to use TB-500 at all are decisions for a licensed clinician who knows your history.
Common questions
How many units is 2.5 mg of TB-500?
With a 5 mg vial in 2 mL of bacteriostatic water (2.5 mg/mL), 2.5 mg is a full 1 mL — 100 units, the entire barrel of a standard insulin syringe. Using less water, or splitting the dose, keeps the draw more practical.
Can BPC-157 and TB-500 be mixed in one syringe?
Combining compounds changes stability and sterility risk and is not something we provide instructions for. This is a question for a licensed clinician.