Healing & injury · Muscle & recovery
TB-500, simplified.
Also called Thymosin beta-4 fragment
Early researchA lab-made piece of a natural repair protein. It is often paired with BPC-157 for injuries.
- Size
- 7 amino acids
- How it is taken
- Injection
- Status
- Research compound, under FDA review
- Available sizes
- Vials: 5 mg, 10 mg · Capsules: 500 mcg
What is it?
Thymosin beta-4 is a protein your cells use to move, build blood vessels and repair damage. TB-500 is a short active piece of it.
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What studies show
- In animalsIt improved wound, muscle and heart repair in animal studies.
- In peopleThe full thymosin beta-4 protein was tested as eye drops and wound gels in people, with modest results. TB-500 itself has not been tested in people.
What we don’t know yet
- Whether the fragment works like the full protein.
- Long-term safety.
Side effects and cautions
- Banned in sport by WADA; horse-racing positives are common.
- Online product quality varies.
Is it legal?
Not FDA-approved. Included in the 2026 HHS compounding plan and reviewed by an FDA advisory committee in July 2026.
Dosage & schedule evidence
How to read published schedules
Third-party protocols are not established clinical dosing standards. Safe human dose, frequency, and duration may be unknown. Research findings may not translate to safe or effective personal use.
| Measurement | Meaning |
|---|---|
| 1 mg | 1,000 mcg (mass) |
| 100 U-100 units | 1 mL (volume, not dose) |
See third-party published protocols ↗ for research context. North Star does not validate these schedules.
Consult your doctor before considering any peptide for personal use. Educational only, not administration guidance.
Common questions
What is TB-500?
A lab-made piece of a natural repair protein. It is often paired with BPC-157 for injuries. Thymosin beta-4 is a protein your cells use to move, build blood vessels and repair damage. TB-500 is a short active piece of it.
What does the research say about TB-500?
It improved wound, muscle and heart repair in animal studies. The full thymosin beta-4 protein was tested as eye drops and wound gels in people, with modest results. TB-500 itself has not been tested in people.
Is TB-500 FDA approved?
Not FDA-approved. Included in the 2026 HHS compounding plan and reviewed by an FDA advisory committee in July 2026.
What are the side effects of TB-500?
Banned in sport by WADA; horse-racing positives are common. Online product quality varies.
Comes in these blends
- BPC-157 + TB-500 (5/5 mg, 10/10 mg vials · 500/500 mcg capsules): BPC-157 + TB-500
- Wolverine (10/10 mg vial): BPC-157 + TB-500
- GLOW (50/10/10 mg, 70/10/10 mg vials): GHK-Cu + TB-500 + BPC-157
- KLOW (50/10/10/10 mg vial): GHK-Cu + TB-500 + BPC-157 + KPV
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This page explains published research in plain language. It is not medical advice, a diagnosis, or a recommendation to take anything, and it does not give dosing. Most peptides here are not FDA-approved, and products sold online vary widely in purity. Rules around peptides are changing, so check the current status and talk with a licensed clinician before starting anything. Last reviewed 2026-10-19.