TB-500
Thymosin beta-4 fragment
A synthetic fragment of thymosin beta-4, studied for cell migration and tissue repair — frequently paired with BPC-157 in repair protocols.
Last reviewed · 1 references
How it works
Thymosin beta-4 is the primary actin-sequestering protein in cells and governs cell migration. TB-500 reproduces its active region. Because repair requires cells to travel to the injury site, promoting migration accelerates several stages of healing simultaneously — alongside reported angiogenic and anti-inflammatory effects.
Animal studies only. Findings come from rodent or in-vitro models. Animal results frequently fail to replicate in people.
What the research reports
- Accelerated wound healing and reduced scarring in animal models
- Cardiac repair after infarction in rodents
- Corneal and dermal healing studies
- Neuroprotection and improved functional recovery after TBI in rats
What it has not been shown to do
- No human efficacy trials for musculoskeletal repair
- Banned by WADA
- No mental-health data of any kind
Dosing reference
Community protocols commonly cite 2–5 mg twice weekly during a loading phase. Not trial-derived.
Calculate my dose for TB-500- Routes studied
- Subcutaneous, Intramuscular
- Half-life
- Longer-acting than BPC-157, which is why twice-weekly dosing is conventional
- Cycle length in the literature
- Loading phase of 4–6 weeks, then reduced frequency
Working out a draw volume from a vial? Use the free reconstitution calculator.
Side effects and contraindications
Reported side effects
- Injection-site reaction
- Lethargy reported anecdotally
- Head-rush sensations
Do not use if
- Active or historic cancer — cell migration promotion is a theoretical metastasis concern
- Pregnancy and breastfeeding
- WADA-tested athletes
The practice that shares the mechanism
Mechanism hubs
- Nerve regenerationPeripheral nerves regenerate at roughly a millimetre a day. The central nervous system largely does not. What that means for peptides and practice.
- Inflammation & moodWhy inflammatory markers are elevated in a subset of depression, what causes it, and which peptides and practices act on the pathway.
Stacks that include it
Common questions
- Not exactly. TB-500 is a synthetic fragment containing the active binding region, not the complete 43-amino-acid protein. Research on the full protein is often cited as though it applies to the fragment, which is a stretch.
Sources & evidence notes
Findings come from rodent or in-vitro models. Animal results frequently fail to replicate in people.
Confidence score 3/100
Preliminary
Mechanism only. Nothing here establishes that a person would feel anything.
- 1.
Annals of the New York Academy of Sciences, 2012 · Source (opens in a new tab)
In vitroLimited gradeCells or tissue in a dish. Tells you about mechanism, not about outcomes.