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Semaglutide half-life calculator

See how Semaglutide accumulates across repeated doses, where the level plateaus, and how long it takes to clear — modelled from published half-life estimates.

Semaglutide has one of the longest half-lives in this class — roughly one week — so weekly doses stack for over a month before levels plateau. Adjust the dose and interval to see that curve.

Estimates for education — not a clinical measurement.

The curve is a simple one-compartment model built on published population half-lives. It is not a plasma concentration, it does not account for your physiology, and it is not dosing advice.

Your schedule

Half-life: 6.9 d · Time to peak: 24 h

Source
FDA prescribing information for Ozempic/Wegovy: terminal half-life ≈ 1 week (~165 h); Tmax 1–3 days after subcutaneous dosing.

Estimated amount in system

Relative active amount from your dose, summed across repeated doses. The dashed line is the steady-state average.

Steady-state peak
1.81 mg
Steady-state trough
1 mg
Accumulation factor
1.98×
Time to steady state
34.4 d
Time to clear
34.4 d
Peak to trough drop
45%

Estimates only. Values are relative amounts, not plasma concentrations.

Semaglutide half-life and accumulation

Each dose of Semaglutide decays exponentially: half is gone after one half-life, three quarters after two. Dose again before the previous dose has cleared and the remainders stack, which is why levels climb for the first few weeks of a protocol before flattening out. That plateau is steady state, and it arrives at roughly five half-lives. The same five-half-life rule describes clearance after the last dose.

FDA prescribing information for Ozempic/Wegovy: terminal half-life ≈ 1 week (~165 h); Tmax 1–3 days after subcutaneous dosing.

Semaglutide half-life FAQ

How long does Semaglutide stay in your system?
As a rule of thumb, about five half-lives after the last dose roughly 97% has been eliminated. Set your dose and interval above to see that figure for the schedule you are modelling.
How long until Semaglutide reaches steady state?
About five half-lives of consistent dosing. Until then, levels are still climbing dose over dose even though nothing about the schedule has changed.

Try the general half-life calculator or browse all free tools.

Read the Semaglutide tracking guide

Semaglutide Half-Life Calculator — Accumulation & Clearance | TrackPep AI