TB-500 half-life and steady state
2 days (estimated) modelled half-life, peaking 4 h after a dose. What that means for how long it lasts, how much it builds up, and when bloodwork is worth drawing.
- Also known as
- Thymosin Beta-4
- Class
- Peptides
- Modelled half-life
- 2 days — estimated half-life, limited human PK data
- Time to peak
- 4 h
- Formulation
- Aqueous (reconstituted powder)
- Cleared per dosing interval
- 70% gone, 30% still present after 3.5 days
- Time to steady state
- ~10 days (about five half-lives)
- Accumulation at that cadence
- 1.42× a single dose
- Peak-to-trough at steady state
- 3.15×
- Regulatory status
- Research compound — no FDA approval. Not for human use label.
- Monitoring panel
- No specific labs. General health panel annually.
- Before mixing
- Sealed powder tolerates room temperature in transit, but keep it refrigerated at 2–8 °C (36–46 °F) for anything beyond a few weeks, or frozen for months. Keep it dark — the carton it shipped in is doing a job.
- After mixing
- Once reconstituted with bacteriostatic water: refrigerate at 2–8 °C and use within about 28 days. The benzyl alcohol in bacteriostatic water is what buys that window — plain sterile water has no preservative, so a vial mixed with it should be treated as one sitting only. Kits are usually ten vials: only the one you mixed is on that 28-day clock — the sealed ones keep their own, much longer shelf life, so store them as powder, not as solution.
- What ruins it
- Do not freeze a reconstituted vial. Repeated freeze–thaw is one of the more reliable ways to degrade a peptide.
- Handling caveat
- General handling practice for this formulation. Your supplier’s own insert or COA overrides anything here.
TB-500's estimated two-day half-life puts it in a different class from BPC-157 despite the two being discussed almost interchangeably. Where BPC-157 is cleared between daily doses, TB-500 at a twice-weekly cadence does accumulate — the interval is under two half-lives, so each dose lands on a meaningful remainder of the last. That is exactly why the schedules for the two differ, and it is the most useful thing to know if you have seen them paired.
As with BPC-157, the half-life is an estimate. TB-500 is a synthetic fragment of thymosin beta-4, a peptide present in most cells, and the published human pharmacokinetic record is thin. The two-day figure is inferred rather than measured, and the accumulation and steady-state numbers below are as uncertain as the input they are computed from.
The loading-then-maintenance pattern in the app's dosing rows is a direct consequence of the accumulation. Twice weekly for several weeks builds a level; once weekly holds it roughly where it got to, because a weekly interval against a two-day half-life is nearly three half-lives and lets most of each dose clear. Whether that pattern achieves anything is a separate question — TB-500 is a research compound with no human approval, its evidence base is animal and in-vitro work, and the systemic rather than local action means the whole dose has to be given at once.
One dose
pkCurve function — a
one-compartment absorption-and-elimination model with the absorption rate fitted so the
peak lands at the published time to peak.Dosed twice weekly
Charted at twice weekly because that is the loading schedule in the app's own dosing rows; maintenance there is once weekly. It is what the numbers below are indexed to, not a recommendation about frequency — that is a prescribing decision.
The arithmetic behind those numbers
fraction left after one interval = 2^(−1.75) = 0.297
accumulation ratio = 1 ÷ (1 − 0.297) = 1.42
time to steady state ≈ 5 × half-life = 10 days
peak-to-trough = simulated, 1.43 ÷ 0.4542 = 3.15
The accumulation ratio is a closed form; the peak-to-trough figure is not. The generator adds up enough repeated curves for the total to stop changing, then reads the highest and lowest points of the last interval — which is what steady state means in practice. The vertical axis is relative, not a concentration: the shape and the ratios carry across people, the absolute levels do not.
This compound's half-life is an estimate. The app flags it, and every number on this page inherits that. It means the published human pharmacokinetic data is limited or absent and the figure is inferred — so treat the curves as the right shape rather than the right numbers, and treat any claim about exact clearance times with the same caution.
Interaction rules that name TB-500
From the app's own interaction data. Not exhaustive, and not a safety clearance — a combination that is not listed is one nobody has documented here, which is not the same as one that is fine. The full combination checker has the rest.
Gold Standard Injury Recovery Combination
BPC-157 and TB-500 are synergistic — BPC-157 acts locally on tissue repair mechanisms while TB-500 promotes systemic cell migration and actin upregulation. Together they represent the most comprehensive peptide approach to injury recovery.
What to watch: No specific labs. Monitor healing progress and injection sites.
The dosing rows this cadence came from
Animal-only or theoretical Reproduced from the app's entry so you can see what the chart above is indexed to. Which row applies to a particular person, if any, is a clinical decision this page does not make.
| Label | Amount | Route and frequency |
|---|---|---|
| Loading | 2-2.5mg twice weekly | SubQ or IM |
| Maintenance | 2-2.5mg once weekly | SubQ |
When to draw bloodwork
The panel the app records for TB-500 is: No specific labs. General health panel annually.. The pharmacokinetic point is the timing rather than the list: after any change, a level takes about 10 days to settle, so a panel drawn sooner measures something still moving. And because the peak-to-trough swing here is 3.15×, when in the interval you draw changes the result materially — a result without a stated draw time relative to the last dose is hard to compare with anything. Whether a result means anything is a question for the clinician who ordered it, read against the reference range your own lab printed. The lab-marker pages cover what the individual analytes measure.
Related: the interactive half-life calculator to try other cadences, and the TB-500 reconstitution calculator.
The app draws this curve from the doses you actually logged — your dates, your cadence — and projects seven days forward from the last one.
Save this dose to your log