What Is TB-500? Dosage, Half-Life & How to Track It
Also known as: Thymosin Beta-4 fragment · TB500 · Tβ4 fragment
TB-500 is a synthetic fragment of thymosin beta-4, a protein your body uses in tissue repair. Unlike BPC-157, it acts systemically — where you inject it barely matters — so it is typically dosed only two to three times a week rather than daily. Community protocols cluster around 2–2.5 mg per shot (roughly 5 mg/week). Educational information only; your protocol is a physician conversation.
What TB-500 is and how it works
TB-500 is a synthetic version of the active region of thymosin beta-4 (Tβ4), a naturally occurring 43-amino-acid protein found in high concentrations in platelets, wound fluid, and immune cells — everywhere your body does repair work.
Its signature mechanism is actin sequestration. By binding G-actin, it promotes cell motility — it helps repair-competent cells migrate toward damaged tissue. Because that signal travels through the whole body, TB-500’s effects are systemic: it doesn’t much matter where you place the injection, unlike compounds that work at the needle tip. It also appears to support VEGF/FGF signaling and to damp inflammatory cytokines.
This is the functional reason TB-500 is so often paired with BPC-157 (the community “Wolverine stack”): BPC-157 builds a favorable repair environment locally while TB-500 mobilizes cells toward it systemically. As with BPC-157, the human evidence is limited — the case is mechanistic and anecdotal, not trial-proven, and it is not FDA-approved for human use.
Typical dosing & reconstitution
TB-500 ships lyophilized and is reconstituted with bacteriostatic water. Two dosing philosophies show up. Product-style protocols run 500–1000 mcg daily; the more common community pattern is 2–2.5 mg two to three times a week (about 5 mg/week), sometimes front-loaded at 5–10 mg/week for the first few weeks of an acute injury before tapering.
Reconstitution options set your concentration and therefore your units:
| Vial | BAC water | Concentration | 1 unit (U-100) ≈ |
|---|---|---|---|
| 5 mg | 3 mL | 1.67 mg/mL | 16.7 mcg |
| 10 mg | 3 mL | 3.33 mg/mL | 33.3 mcg |
At 1.67 mg/mL, a 2 mg dose is 120 units — more than a standard 1 mL insulin syringe holds — so a dose that size is either split or drawn at a higher concentration (a 10 mg vial in 3 mL puts 2 mg at 60 units). That interplay between vial size, water, and dose is exactly what the reconstitution calculator resolves.
Half-life & what it means for frequency
TB-500 clears from the blood relatively quickly, but here is the nuance that matters: its tissue-level effects outlast its blood half-life. The cell-migration signal it sets off persists after the compound itself is gone, which is why a 2–3×-weekly schedule is enough and daily dosing isn’t necessary.
That is the opposite of BPC-157, where a short half-life forces daily dosing. With TB-500 the biology does the smoothing for you. Loading phases — higher weekly totals early, then a maintenance taper — lean on this: you are building up tissue-level activity, not chasing a blood level.
What to track & common side effects
TB-500 is generally reported as well tolerated; the most common issues are injection-site reactions and occasional fatigue or head-rush after a dose. The same pro-angiogenic cancer caution as BPC-157 applies — an active or recent cancer history warrants a doctor’s input first.
Because dosing is only a few times a week, the easy thing to lose track of is “did I actually pin on Monday?” — and, with loading-then-taper protocols, which phase you are in. Logging each shot and the recovery outcome you are chasing keeps both honest.
How to track TB-500 in Stackeddd
Log TB-500 on its 2–3×-weekly cadence and the calendar does the remembering for you — no more “was that Monday or Tuesday?” Track the injury or recovery marker alongside it so you can see whether the loading phase is actually moving the needle. Get the reconstitution right first, so 2 mg is really 2 mg.
Model it yourself · free, no account
Reconstitution Calculator
Model it yourself: enter your vial size and BAC water and the Peptides tab returns concentration and the exact units for any dose — including whether a big dose overflows a 1 mL syringe. The same math built into the Stackeddd app.
Related compounds
Related reading: What peptides can you mix in the same syringe? · Peptide reconstitution math: how much BAC water to add
Frequently asked questions
What is TB-500 used for?
TB-500 is studied for systemic tissue repair and recovery — mobilizing repair cells toward injured tissue via actin binding, plus anti-inflammatory and blood-vessel effects. Evidence is largely preclinical and anecdotal; it is not FDA-approved for human use.
What is the half-life of TB-500?
Its blood half-life is short (hours), but its tissue-level effects persist noticeably longer than the compound stays in circulation. That is why a twice-to-thrice-weekly schedule works and daily dosing is unnecessary.
How often do you inject TB-500?
Typically two to three times per week — commonly 2–2.5 mg per shot for around 5 mg/week. Acute-injury protocols sometimes front-load 5–10 mg/week for a few weeks, then taper to a maintenance dose.
Can you mix TB-500 and BPC-157 in the same syringe?
Community practice is to draw each from its own vial into a single insulin syringe for one injection — separate vials are preferred over a fixed-ratio blend so each dose can be adjusted independently. See our syringe-compatibility guide for the full rundown.
This is educational information, not medical advice. Doses and protocols above reflect published references and community practice — protocol decisions belong with your prescribing physician. Generic names used throughout. How this reference is built & how the AI is tested →
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