TB-500 Half-Life Calculator
TB-500's half-life is short — a matter of hours — which is worth knowing because it is commonly discussed on intervals of days. This calculator charts what that gap does to the curve.
Half-life 1.5 hours · peaks at 4 hours
Every 3.5 days.
Half-life
Left at next dose
TB-500 · twice weekly · levels plateau after ~7.5 hours
Steady-state peak
0.97 mg
Steady-state trough
0 mg
Accumulation
None
At twice weekly, each dose has essentially cleared before the next one — levels don't accumulate, they repeat the same rise and fall. Clearance after a dose takes about 7.5 hours.
This is a modelled estimate of relative levels from published half-life and time-to-peak figures — not a measured blood concentration. Individual pharmacokinetics vary.
Based on a published TB-500 half-life of about 1.5 hours. The chart models RELATIVE levels from a unit dose — enter your own figures to see the shape. It is not a dose recommendation.
Never do this math twice.
The Pep AI app remembers your vials and doses, shows an interactive syringe you draw to, counts down the doses left in each vial, and reminds you when it's time. Free on iOS and Android.
What a 1.5 hours half-life means in practice
A half-life of 1.5 hours against twice a week dosing means each dose has essentially cleared before the next arrives. That shapes the curve in three ways:
1. One half-life
Half the dose is gone after 1.5 hours. After two half-lives 25% remains, after three 12.5%.
2. What's left at the next dose
Dosing twice a week means the next dose lands 3.5 days later, with about 0% of the previous one still present.
3. Accumulation and plateau
Almost nothing carries over, so levels don't accumulate — each dose repeats the same rise and fall, clearing in about 7.5 hours.
Worked example
TB-500 has a half-life of 1.5 hours. Dosing twice a week, the next dose arrives 3.5 days later with about 0% of the previous one still on board. That's little enough that levels don't build up: each dose rises and falls on its own, clearing in about 7.5 hours.
A fragment, and a short one
TB-500 is a synthetic peptide based on an active region of thymosin beta-4, a naturally occurring 43-amino-acid protein. It is not the protein itself, and research conducted on full-length thymosin beta-4 does not automatically describe the fragment.
Its reported half-life is measured in hours, which means that on any multi-day interval each administration has cleared entirely before the next. There is no accumulation and no plateau — the curve is a series of independent spikes rather than a rising baseline. Any argument that intervals of days make sense has to rest on downstream effects outlasting the molecule, not on the molecule persisting.
Frequently asked questions
This calculator is provided for informational and educational purposes only and is not medical advice. Always confirm dosing with a qualified healthcare professional and double-check your own measurements before administering anything.
Built by the Pep AI team.