HCG half-life and pharmacokinetics chart
Pre-filled plasma half-life model for HCG. See how a 33 hours half-life affects steady state, accumulation, peak-trough swing, and clearance timing.
Preset values: 2500 IU-eq every 3 days, half-life ~33 hours.
Plasma half-life of ~33h supports every-other-day or twice-weekly microdosing for HPG support.
Open interactive chart →Why these values?
The half-life used here (33 hours) is the published or well-established estimate for HCG from pharmacokinetic studies. The default dose (2500 IU-eq) and cadence (every 3 days) reflect typical standard protocols — not a prescription or recommendation. Your specific product's label and your clinician's protocol override any default here.
Accumulation. With a half-life of 33 hours and dosing every 3 days, the ratio τ/t½ = 2.18 gives an accumulation factor of ~1.28×. That means the steady-state peak plasma mass is about 1.3× the mass of a single dose.
Time to steady state. Approximately 5 half-lives (~6.9 days) of consistent dosing before average concentration stops rising. Dose-escalation protocols that change doses before this point are titrating against a still-rising baseline, which is one reason weekly peptides feel "slow" at the start.
How long does HCG stay in your system?
After a single dose, half of the HCG is gone in about 33 hours, 97% is cleared in about 7 days (five half-lives), and under 1% remains after about 9.1 days.
| Cleared | Remaining | Half-lives | Time after one HCG dose |
|---|---|---|---|
| 50% | 50% | 1 | 33 hours |
| 75% | 25% | 2 | 2.8 days |
| 90% | 10% | 3.3 | 4.6 days |
| 97% | 3% | 5.1 | 7 days |
| 99% | 1% | 6.6 | 9.1 days |
Between doses. At every 3 days, doses land 2.18 half-lives apart, so about 22% of the peak is still present when the next dose goes in. The steady-state swing in this model runs from ~3207 IU-eq at peak to ~707 IU-eq at trough — a moderate swing with meaningful carry-over from one dose to the next.
A first-order, one-compartment model: it leaves out absorption delay from the injection depot, protein binding and individual differences in clearance, and effects can outlast plasma levels. Good for dosing rhythm; not clinical pharmacokinetics.
HCG half-life FAQ
What is the plasma half-life of HCG?
This chart uses an estimated HCG plasma half-life of about 33 hours. Published values can vary by formulation, route, assay, and study design.
How long until HCG reaches steady state?
A simple first-order model reaches practical steady state after about five half-lives, which is roughly 6.9 days for HCG.
How long does HCG stay in your system?
After a single dose, half of the HCG is gone in about 33 hours, 97% is cleared in about 7 days (five half-lives), and under 1% remains after about 9.1 days. Those are plasma estimates from a half-life of 33 hours; effects can outlast plasma levels, and detection windows depend on the assay.
How much HCG is left when the next dose is due?
Dosing every 3 days is 2.18 half-lives apart, so about 22% of the peak level remains at the next dose. At steady state that means a peak of ~3207 IU-eq and a trough of ~707 IU-eq in the model.
Does this HCG pharmacokinetics chart recommend a dosing schedule?
No. It visualizes half-life, accumulation, peaks, and troughs from values you enter. It is not a prescription, dose recommendation, or substitute for the product label or clinician guidance.
Why does steady state matter for HCG?
Steady state explains why long-half-life compounds can keep rising for weeks after starting or changing a dose, while short-half-life compounds behave more like brief pulses.
Related for HCG
Half-life charts for related peptides: CJC-1295 (8 days), Hexarelin (1 hour), HGH (Somatropin) (2.5 hours), HGH Fragment 176-191 (2 hours).
Track your real HCG protocol
Peptide Protocol logs every actual injection time and shows your real timeline — not a model. Side-effect tracking included.
Get the iPhone app →Educational use only. Nothing on this page constitutes medical advice. Pharmacokinetic parameters are published estimates; individual PK varies. Use label values and consult a clinician for any dosing decision.
Educational use only. Peptide Protocol is an informational tool. Nothing on this page constitutes medical advice. Many peptides are prescription-only or restricted in your jurisdiction. Always consult a licensed healthcare professional before injecting any compound.