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The Peptide Effect
preclinicalHealing & Recovery

TB-500

Also known as: Thymosin Beta-4, Tβ4, Thymosin Beta 4 Fragment

TB-500 is a synthetic version of Thymosin Beta-4, a 43-amino acid peptide naturally present in virtually all human cells. It plays a critical role in tissue repair, cell migration, and blood vessel formation. TB-500 is widely used in healing protocols for its ability to reduce inflammation and promote repair of injured muscles, tendons, and ligaments.

Key Facts

Mechanism
TB-500 upregulates the cell-building protein actin, which is essential for cell migration and wound healing. It promotes angiogenesis, reduces inflammation by downregulating inflammatory cytokines, and supports stem cell maturation. The peptide is small enough to travel through tissues with high systemic bioavailability, allowing it to target injury sites throughout the body.
Research Status
preclinical
Half-Life
~6–8 hours
Molecular Formula
C₂₁₂H₃₅₀N₅₆O₇₈S
Primary Use
Healing & Recovery

Benefits

  • Promotes repair of injured muscles, tendons, and ligamentsstrong
  • Reduces inflammation and supports immune modulationstrong
  • Stimulates new blood vessel growth (angiogenesis) at injury sitesstrong
  • Enhances flexibility and reduces muscle spasm and stiffnessmoderate
  • Supports cardiac repair and reduces fibrosis after heart injurymoderate
  • Promotes hair regrowth via stimulation of stem cells in hair folliclespreliminary
  • May improve wound healing and reduce scar tissue formationmoderate

Dosage Protocols

RouteDosage RangeFrequencyNotes
Subcutaneous injection2.0–2.5 mg2× per week (loading), 1× per week (maintenance)Loading phase: 2× weekly for 4–6 weeks, then reduce to maintenance
Intramuscular injection2.0–2.5 mg2× per weekCan inject near (not into) injury site for localized benefit

Medical disclaimer

Dosage information is provided for educational reference only. Always follow your prescriber's instructions and consult a qualified healthcare provider before starting any peptide protocol.

Side Effects

  • Injection site irritation or rednesscommon
  • Temporary lethargy or fatiguecommon
  • Headacherare
  • Mild nausearare
  • Rush of blood to the head (vasodilation effect)rare

Frequently Asked Questions

What is the difference between TB-500 and Thymosin Beta-4?
TB-500 is a synthetic fragment of the full Thymosin Beta-4 (Tβ4) protein. It contains the active region responsible for most of Tβ4's healing properties — specifically the actin-binding domain. They are often used interchangeably in the peptide community, though TB-500 is the version typically available for research purposes.
How does TB-500 compare to BPC-157 for healing?
Both promote healing but through different mechanisms. BPC-157 works primarily through local angiogenesis and growth hormone receptor upregulation — best for localized injuries. TB-500 works systemically via actin upregulation and cell migration — better for widespread or hard-to-reach injuries. Many practitioners stack them together for synergistic healing.
How long does a typical TB-500 protocol last?
A standard protocol involves a 4–6 week loading phase (2.0–2.5 mg twice weekly), followed by a 2–4 week maintenance phase (2.0–2.5 mg once weekly). Total cycle length is typically 6–10 weeks. Improvements are usually noticed within 2–3 weeks.
Is TB-500 banned in sports?
Yes. TB-500 (Thymosin Beta-4) is banned by WADA (World Anti-Doping Agency) under the category of peptide hormones and growth factors. It is prohibited both in-competition and out-of-competition. Several athletes have received suspensions for its use.
Does TB-500 need to be injected near the injury site?
Not necessarily. Unlike some peptides, TB-500 is systemically active — it can travel through tissues to find injury sites regardless of injection location. However, some practitioners prefer injecting near the injury area for potentially faster local effects.

References

  1. 1
    Thymosin beta4 activates integrin-linked kinase and promotes cardiac cell migration, survival and cardiac repair(2004)PubMed ↗
  2. 2
    Thymosin β4 promotes angiogenesis and wound healing(2006)PubMed ↗
  3. 3
    The role of thymosin beta-4 in tissue repair and regeneration(2012)PubMed ↗
  4. 4
    Thymosin β4 and its degradation products in wounds(2017)PubMed ↗

Last updated: 2026-02-14