TB-500
Also known as: Thymosin Beta-4 · TB4 · Tβ4
TB-500 is a synthetic fragment of thymosin beta-4, a naturally-occurring 43-amino-acid peptide. Often stacked with BPC-157 for recovery. Not approved for human use; banned in competitive sport by WADA.
Last reviewed · Panya.health editorial
Panya scores vendors against an 11-signal rubric. Vendors at or above 70 out of 100 are routable; below 70 are documented but get no Panya affiliate link. For prescription peptides like Mounjaro and Wegovy, Panya routes today through licensed clinicians. For research peptides like TB-500, vendor scorecards land in a follow-up sprint after legal review and payment processor selection. Until then, the page surfaces commonly-mentioned vendor names so adults can do their own diligence. We do not yet earn commission on any TB-500 vendor.
Not medical advice. TB-500 is not approved for human medical use in most jurisdictions. The data below is what users do; it is not what regulators have validated. You decide your risk profile.
What it does, and how
Thymosin beta-4 is a real protein abundant in human cells, particularly platelets. TB-500 specifically refers to a synthetic derivative containing the active 4-amino-acid sequence (LKKTETQ or related) marketed in the research-chem space. Animal work shows effects on actin sequestration, cell migration, and tissue repair, with the most-cited applications being cardiac repair after infarction and corneal wound healing. The mechanism in tendon and ligament repair is hypothesised to be similar (cell migration to the injury site, matrix remodelling). Human trial data is sparse; cardiac trials have been small and inconclusive.
Typical practice
Community practice runs 2 mg twice weekly for 4 to 6 weeks as a 'loading' phase, then 2 mg per week as maintenance for another 4 to 6 weeks. Subcutaneous injection is standard. Some users report better results dosing closer to the injury (peri-injury) but TB-500 has a longer half-life than BPC-157 (estimated tens of hours), so systemic dosing is more common. Reconstitution typically 5 mg vial in 5 mL bacteriostatic water.
The dosing above is community practice, not a regulator-validated protocol. Trial-validated dosing for TB-500 in humans does not exist for most use cases listed.
Risks and contraindications
Side effects in user reports are similar to BPC-157: mild injection-site reactions, occasional fatigue or lethargy in the first few days. Theoretical concerns: TB-500 affects cell proliferation and migration, so cancer patients or anyone with a recent cancer history should consult an oncologist before use. Cardiovascular trials have not been definitive but no major safety signals emerged in the small studies done. WADA bans TB-500 in competitive sport. Pregnancy and breastfeeding: avoid. Drug interactions: not characterised. As with BPC-157, the long-term human safety record is unknown.
Where this stands legally
Not FDA-approved for human use. Research-chemical sale is widespread; human use is on the user. Equine use is widespread in racing and TB-500 is on most racing-jurisdiction prohibited lists.
Not a controlled substance. MHRA does not regulate research peptides; customs scrutiny on imports has increased through 2025.
Not on EMA's approved list. WADA-prohibited in competition.
TGA treats unscheduled peptides as prescription-required for personal import; standard ABF customs scrutiny applies.
Not formally scheduled. Sold by Bangkok research-chem channels and some wellness clinics.
Prescription-only by default per MOHAP. Personal import requires documentation.
Where users say they source it
Names below are sourced from community discussion. None are currently scored against the Panya 11-signal rubric. Panya does not earn commission on any of these. You can search them yourself; treat the list as a starting point for your own diligence, not an endorsement.
- Pure RawzPending Panya 11-signal audit
- Limitless LifePending Panya 11-signal audit
- Amino AsylumPending Panya 11-signal audit
- Bangkok wellness clinics offering peptide protocolsPending Panya 11-signal audit
Full vendor scorecards for TB-500 land in a follow-up sprint after lawyer review and payment processor selection. We will not route users to any vendor that scores below 70 on the rubric.
Papers worth reading directly
People asking adjacent questions
BPC-157 if your injury is tendon, ligament, or gut. TB-500 if it's soft tissue (muscle tear, joint capsule). Stacking both is the community default but the human evidence does not ...
If you have a specific tendon or joint injury that has plateaued on conservative management and you accept that the human evidence is thin, then yes, on a defined 4 to 6 week cycle...
Panya blog posts
The phrase on every grey-market peptide site. What it actually means, what it does not mean, and why reading it wrong costs people money.
The five things that matter on a COA, the three things that do not, and the one question that separates a serious vendor from a cargo-cult operator.
The clinic route costs more and takes longer. The research-chem route puts more on you. Neither is wrong. Here is how to choose.
Adjacent reading
Track TB-500 in your peptide journal.
Panya users log their full stack at panya.health/journey. Public-by-default with per-entry privacy controls. Vote-validated by the community.