TB-500
Synthetic fragment of thymosin beta-4, used for whole-body recovery.
Overview
TB-500 is a synthetic version of the active region of thymosin beta-4, a protein that regulates actin (the cell's scaffolding). Animal work shows faster wound, heart and tendon repair. It is popular with athletes and banned in competition.
How it works
Binds actin, helping cells migrate to injured tissue; promotes angiogenesis and reduces inflammation in models. Full-length thymosin beta-4 has been studied in dry eye and wound healing trials; the TB-500 fragment itself has little human data.
Evidence
2/5
Full-length Tβ4 has some human trials (eye, wound); TB-500 fragment is mostly animal and anecdotal.
Half-life
Not well characterized; dosed twice weekly by convention
Known as
Thymosin Beta-4 fragment, Tβ4 (Ac-SDKP / LKKTETQ region)
Compound facts
- Type
- Endogenous peptide/synthetic analog
- CAS Number
- 77591-33-4
- Molecular Weight
- 4,963 Da
- Amino Acids
- 43
- Active Region
- Ac-SDKP (N-terminal)
- Key Sequence
- 17LKKTET22 (actin binding)
Reported benefits
Systemic soft-tissue recovery
Faster repair of muscle and tendon in animals; users report less lingering soreness.
Wound & skin repair
Tβ4 accelerated wound closure in rodent and early human studies.
Flexibility / range of motion
Commonly reported by users after chronic injury.
“Anecdotal” means reported by users, not shown in controlled trials.
Community-reported regimens
Not recommendations. These are commonly cited ranges, shown so you can see what real-world use looks like.
| Plan | Dose | Frequency | Duration | Route |
|---|---|---|---|---|
| Loading phase Often split as 2–2.5 mg per injection. | 2000 mcg | 2× per week | 4–6 weeks | Subcutaneous |
| Maintenance | 2000 mcg | Once weekly or every other week | As needed | Subcutaneous |
Reconstitution calculator
Set up for TB-500. Switch peptide or vial size any time.
1Mix
Add 2 mL water for 5 mg/mL
2Draw
Draw to 40 units = 0.4 mL = 2 mg
Drag the plunger to set your dose.
3Inject
Next site
Right belly, upper
Tap a site after you inject to keep a rotation.
Pinch the skin, stay 2 in. from the navel, then into a sharps bin.
- Doses per vial
- 5
- Vial lasts
- 18 days
- Good once mixed
- ~28 days
- Syringe
- 50-unit, 0.5 mL
Math only: concentration (mg/mL) = vial mg ÷ mL of water; units = dose (mg) ÷ concentration × 100. Always double-check against your own vial label and a clinician. This tool does not recommend a dose.
Reconstitution
Diluent: Bacteriostatic water (0.9% benzyl alcohol) — allows multiple draws from one vial.
- Wipe both vial tops with an alcohol swab and let dry.
- Draw the diluent, then inject it slowly down the inside wall of the vial — never straight onto the powder.
- Swirl gently or let it sit; do not shake. Foam can damage peptides.
- Solution should be clear. Cloudy, stringy or discolored = discard.
- Common mix: 5 mg + 2 mL = 2.5 mg/mL (2 mg = 80 units).
Storage
Powder
Freezer / fridge
Keep sealed vial in the freezer (−20 °C) for long-term storage; fridge (2–8 °C) is fine for a few weeks. Keep dry and out of light.
After mixing
~28 days
Refrigerate at 2–8 °C. Never freeze after mixing. Keep upright, capped, and out of light.
Travel
Keep cool
Short trips at room temperature are generally fine for powder; keep mixed vials cold.
- Large injection volumes at 2 mg — consider mixing with less diluent so the dose fits comfortably.
Side effects & cautions
Reported side effects
- Head rush or lightheadedness
- Temporary fatigue
- Injection-site irritation
- Unknown long-term effects
Cautions
- Theoretical tumor-growth concern (promotes cell migration/angiogenesis).
- Prohibited by WADA.
- Product identity varies — TB-500 is not always the same fragment as full Tβ4. Insist on a certificate of analysis.
FDA & international status
Not FDA-approved
Neither TB-500 nor thymosin beta-4 is approved. Full-length Tβ4 has been in clinical trials (dry eye) but has no approval. It was in FDA compounding Category 2 until April 2026; in July 2026 an FDA advisory committee voted to recommend adding it to the 503A bulks list, with a final decision pending. Sold as research chemical only.
Regulations change often — verify with the FDA, EMA, MHRA, Health Canada, TGA and WADA before acting.
Often paired with
BPC-157Complementary: BPC-157 local, TB-500 systemic. Often run together for 4–6 weeks.
Where to buy
| Size | Price | Per mg | Stock | Latest COA |
|---|---|---|---|---|
| 10 mg | $39.99 | $4.00 | In stock | 99.51% pure, lot TB0002 ILS Labs, tested 2026-07-30 |
Amino Club list prices as of 2026-10-07, before promo codes. Multi-buy: 2+ units 5% off, 3+ units 7.5% off, 10+ units 40% off. Prices change; confirm on the product page. Mixing? Their bacteriostatic water is Amino H2O from $19.99.
TB-500 at Amino Club
Check sizes, current price and the certificate of analysis (COA) on the product page. Sold for in-vitro research only.
Get TB-500 alerts
An email when its price drops, a sale starts, or its FDA or WADA status changes.
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- Look for a batch-specific COA with HPLC purity (≥98%) and mass-spec identity.
- Typical vial sizes: 5, 10 mg.
FAQ
Is TB-500 the same as thymosin beta-4?
No. TB-500 usually refers to a shorter synthetic fragment. Effects of the fragment may differ from the full protein.
Why the loading phase?
It's community convention rather than science: higher early dosing, then taper to maintenance.