BPC-157
BPC-157 Half-Life: Why You Dose Daily
BPC-157 has a ~4-hour half-life. This guide explains what that means for dosing frequency, once vs. twice daily protocols, comparison to other compounds, and the half-life chart.
Informational only. Not medical advice. Consult a licensed healthcare provider before starting, changing, or stopping any protocol.
BPC-157 half-life: the short answer
BPC-157 has an estimated half-life of approximately 4 hours in vivo (in the body). This means roughly half of an injected dose is cleared every 4 hours. After approximately 20 hours (5 half-lives), less than 5% remains active. This is why protocols call for once- or twice-daily dosing, not weekly.
What half-life means in practice
Half-life (t½) is the time it takes for the active concentration of a compound to fall by 50%. The formula:
Concentration at time t = Initial dose × 0.5^(t ÷ t½)
For BPC-157 with a 4-hour half-life, starting from a 250 mcg dose:
| Hours after injection | Half-lives elapsed | Approximate % remaining | mcg active (250 mcg dose) |
|---|---|---|---|
| 0 | 0 | 100% | 250 mcg |
| 4 | 1 | 50% | 125 mcg |
| 8 | 2 | 25% | 62.5 mcg |
| 12 | 3 | 12.5% | 31.3 mcg |
| 16 | 4 | 6.25% | 15.6 mcg |
| 20 | 5 | 3.1% | 7.8 mcg |
| 24 | 6 | 1.6% | 3.9 mcg |
See this curve interactively in the My Pep Calc half-life chart — set your actual dose and dosing schedule to see overlapping active concentration across multiple injections.
Once-daily vs. twice-daily dosing
With a 4-hour half-life and once-daily injections, the trough before each dose (what's active right before you inject again) is roughly 1.6% of the peak. For practical purposes, you're starting nearly fresh each day.
With twice-daily injections (every 12 hours), the trough before the second dose is approximately 12.5% of the first dose — a modest amount still active when you re-dose. This creates slightly higher continuous coverage throughout the day compared to once-daily.
Whether once- or twice-daily is appropriate for your protocol is a question for your prescribing provider. The half-life chart can show you both scenarios visually with your actual dose.
How this compares to other compounds
BPC-157's 4-hour half-life is short relative to most compounds in this class:
| Compound | Half-life | Typical dosing frequency |
|---|---|---|
| BPC-157 | ~4 hours | Once or twice daily |
| CJC-1295 (no DAC) | ~30 minutes | Once or twice daily (pulsed) |
| Ipamorelin | ~2 hours | Once or twice daily |
| CJC-1295 (with DAC) | ~6–8 days | Once or twice weekly |
| Tirzepatide | ~5 days (120 hours) | Once weekly |
| Semaglutide | ~7 days (168 hours) | Once weekly |
| TB-500 | ~24 hours | Variable (loading/maintenance) |
This difference in half-life is why running a multi-compound stack requires per-compound dose tracking — each compound has its own rhythm. A CJC-1295/BPC-157 combination requires daily injections of both; adding a weekly tirzepatide dose means a different injection day entirely.
Why half-life matters for injection timing
For BPC-157, the short half-life means injection timing within the day matters less than for CJC-1295/Ipamorelin (where fasted-state timing significantly affects GH pulse size). BPC-157's mechanism — involving nitric oxide synthase pathways and growth factor modulation — is not meaningfully affected by fed vs. fasted state.
What does matter: consistency. Taking BPC-157 at roughly the same time each day (or at two consistent times for twice-daily) makes the dose log meaningful and helps identify patterns over the protocol's duration.
A note on half-life estimates
The ~4-hour half-life estimate for BPC-157 is derived from preclinical research. Robust human pharmacokinetic data (formal PK studies in humans) is limited for most compounded peptides. The value is an approximation, not a precise clinical measurement. Your actual clearance rate can be affected by injection route (SubQ vs. IM), injection site, body composition, and individual metabolism.
This is one reason the half-life chart is labeled as a visualization tool, not a clinical measurement — it helps you understand the pattern, not predict your exact blood level at a given hour.
Frequently asked questions
- How long does BPC-157 stay in your system?
- Based on a ~4-hour half-life, approximately 97% of a BPC-157 dose is cleared within 20 hours (5 half-lives). After 24 hours, less than 2% remains active. For practical purposes, BPC-157 does not accumulate meaningfully between once-daily doses.
- Should I take BPC-157 in the morning or evening?
- For BPC-157, timing relative to meals is less critical than for GH secretagogues like CJC-1295/Ipamorelin. Consistency matters more than a specific time window. Many protocols call for once daily in the morning; twice-daily protocols split between morning and evening.
- Does BPC-157 need to be cycled?
- This is a protocol design question for your prescribing provider, not a calculator. Common protocol lengths reported in the community range from 4–12 weeks, sometimes with an off period before resuming. My Pep Calc tracks your protocol timeline so you can see exactly how long you've been on.
- How is BPC-157 half-life different from TB-500?
- BPC-157 has an estimated 4-hour half-life. TB-500 (Thymosin Beta-4) has an estimated half-life of approximately 24 hours. This is why TB-500 is often dosed on a loading/maintenance schedule (e.g., twice weekly for 4–6 weeks, then once weekly) rather than the daily injection schedule typical for BPC-157.
Sources
- Sikiric P, et al. The antidote for amphetamine toxicity — stable gastric pentadecapeptide BPC 157. Toxicol Rep. 2020;7:1266-1278.
- Sikiric P, et al. Stable gastric pentadecapeptide BPC 157: novel therapy in gastrointestinal tract. Curr Pharm Des. 2011;17(16):1612-32.
- Vukovic S, et al. BPC-157 and standard care in the treatment of superior mesenteric artery syndrome. J Physiol Pharmacol. 2018;69(5).
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