Key Takeaways
- There is no clinically established human dosage for TB-500. No human trials have tested one.
- TB-500 dosage charts circulating online come from vendors and forums, not clinical research.
- Animal studies have used specific amounts, but those don't translate into a human injectable dose.
- On a prescription, the dose comes from your clinician, and the pharmacy label lists the strength, concentration, and schedule.
- TB-500 is prohibited at all times under WADA's anti-doping rules.
There's no established TB-500 dosage: no completed trial has tested one, and the FDA's review found no human exposure data for it by any route.
TB-500 isn't FDA-approved, and all of its direct research comes from animals and lab dishes. No human trial has tested a dose, so there's no dosing data from people to build on.
What TB-500 is
TB-500 commonly refers to the N-terminal acetylated, 17-23 fragment of thymosin beta-4, with the sequence Ac-LKKTETQ. A 2012 analytical study identified this fragment in TB-500 using mass spectrometry.
TB-500 and full-length thymosin beta-4 are related, but they are not interchangeable. Full-length thymosin beta-4 contains 43 amino acids, while TB-500 has a much shorter, seven-amino-acid fragment.
Direct TB-500 research is still limited. A 2024 study evaluated TB-500 metabolism and metabolites in rats, human serum systems, and fibroblast assays. The authors noted that the biological effects of TB-500 itself had not been documented.
Animal research also exists for the seven-amino-acid LKKTETQ actin-binding domain. In aged mice, this fragment promoted wound repair, but that does not establish a human TB-500 dosing schedule.
TB-500 dosage: what research has used
No human clinical trial has ever tested a TB-500 dose in people. The only data comes from animal and lab studies, and neither tested a human injection.
Reading your pharmacy label
On Rebody prescriptions, the pharmacy label lists the strength, concentration, directions, storage, and beyond-use date. Follow the label, not a forum chart or another vendor's directions.
Syringe units measure volume, so the same number of units delivers a different amount at a different concentration. If the math on your label is unclear, ask the dispensing pharmacy before your first dose.
TB-500 and BPC-157
TB-500 and BPC-157 are frequently discussed together, sometimes as the “Wolverine stack.” FDA's review found two complaint reports about blended TB-500 and BPC-157 products, and neither included a safety assessment. There's no established human dosing standard for either compound alone or combined.
Where TB-500 stands with the FDA
TB-500 sat in the FDA's Category 2, substances the agency says raise significant safety concerns, until April 2026, when the FDA removed it for review by its Pharmacy Compounding Advisory Committee. On July 23, 2026, that committee voted 8 to 6 to recommend adding TB-500 to the 503A bulks list, the list of substances compounding pharmacies can use. FDA staff had recommended against it.
Safety and side effects of TB-500
FDA's review found no published human safety data for TB-500 and no case reports. Its search of FDA's adverse event database returned no reports.
Any injection carries ordinary risks such as pain, bruising, irritation, and infection. Tell your prescriber about any of the following before starting:
- Pregnancy or breastfeeding
- Cancer or immune treatment
- Clotting concerns
- Other medications you take
Anti-doping status
TB-500 is prohibited at all times under the World Anti-Doping Agency's Prohibited List, named under S2.3, growth factors and growth factor modulators, alongside thymosin beta-4. Tested athletes should treat it as off-limits regardless of how or where it's sourced.
What the evidence supports
There's no standardized human TB-500 dosage. No completed human trial has tested one, and the FDA's review found no human exposure data for TB-500 by any route.
Schedule a consult to talk with a Rebody provider about TB-500 and your recovery goals.
Frequently Asked Questions (FAQs):
What is the correct TB-500 dosage?
There isn't a clinically established one. No human clinical trial has tested a TB-500 dose, so nothing qualifies as a clinically established amount. The loading and maintenance charts you'll find online come from vendors and forums extrapolating from animal and lab research, not from data on people. On a prescription, a licensed clinician sets the dose and the pharmacy label lists it.
What's the difference between TB-500 and thymosin beta-4?
Thymosin beta-4 is the full-length, 43-amino-acid protein your body makes naturally. TB-500 is a short synthetic fragment of it (residues 17-23, Ac-LKKTETQ), built around the piece responsible for binding actin.
Is TB-500 banned for athletes?
Yes. WADA lists TB-500 by name under S2.3, prohibited growth factors and growth factor modulators, prohibited at all times, in and out of competition.