For semaglutide, about 5 to 7 weeks. That figure is not a rule of thumb — it is printed in the Wegovy label: with an elimination half-life of approximately 1 week, semaglutide will be present in the circulation for about 5 to 7 weeks after the last injectable dose of 2.4 mg or 7.2 mg. The Ozempic label, whose maximum dose is 2 mg, says about 5 weeks.
Other GLP-1 drugs are not comparable to it, and the spread is wide — liraglutide is gone in about three days.
Half-life and clearance, by compound
Half-lives are label figures, except retatrutide, which has no label and is taken from the published phase 1 and phase 2 trials. “Practically gone” is the five-half-life convention described below — the only derived number on this page.
Where “practically gone” comes from
Each half-life removes half of what is left. After five of them roughly 3% of the original amount remains, which is the conventional point at which a drug is treated as cleared. It is a pharmacology convention, not a regulatory statement, and no label publishes it as a number.
It is worth applying anyway, because in the one case where a label does state a clearance time, the two agree: five one-week half-lives is five weeks, and the Ozempic label says about 5 weeks after the last dose.
The Wegovy figure runs longer — 5 to 7 weeks — for a reason that is easy to misread. The half-life is unchanged. The dose is up to three times higher, so the concentration starts from a higher point and takes longer to fall to the same low level. A higher dose does not clear more slowly; it simply has further to fall.
Can you get it out of your system faster?
No, and the label is unusually direct about it. The overdose section instructs supportive treatment according to clinical signs and symptoms, and warns that a prolonged period of observation and treatment may be necessary, taking into account the long half-life of approximately 1 week. There is no antidote and no reversal agent — the management of too much semaglutide is waiting, under observation.
The pharmacokinetics explain why nothing intervenes usefully:
- It is bound to albumin. More than 99% of circulating semaglutide is bound to plasma albumin, which the label notes results in decreased renal clearance and protection from degradation. Bound drug is not filtered by the kidney.
- Almost none leaves intact. Approximately 3% of a dose is excreted in urine as intact semaglutide. The primary route of elimination is metabolism — proteolytic cleavage of the peptide backbone and sequential beta-oxidation of the fatty acid sidechain.
- It is not stored in fat. The mean volume of distribution is about 12.5 L, which is roughly extracellular fluid. There is no tissue depot to sweat, burn or starve out.
- Organ function barely moves it. The label reports no clinically significant difference in semaglutide pharmacokinetics in renal impairment down to an eGFR of 30, or in mild, moderate and severe hepatic impairment (Child-Pugh A–C). If failing kidneys and a failing liver do not change the clearance rate, water, exercise and sauna will not either.
The one place a label converts half-life into an instruction
Pregnancy. The Wegovy label instructs discontinuing semaglutide at least 2 months before a planned pregnancy, explicitly because of the long half-life. That is a wider margin than the 5 to 7 weeks the pharmacokinetics section gives, and it is the only worked example of the half-life being turned into a date anywhere on the label.
Retatrutide
Retatrutide’s reported terminal half-life is roughly 5 to 7 days, which is what supports once-weekly dosing in its trials. That number comes from published trial pharmacokinetics rather than from a label, because there is no label: retatrutide is not approved by the FDA, EMA, MHRA, TGA or Health Canada, and no approved human dose exists in any country.
A half-life is a property of the molecule and is reportable. A dosing schedule is not, and this site does not publish one for retatrutide. Retatrutide status and published study doses.
Related
- How long semaglutide takes to work — the same pharmacokinetics read forwards instead of backwards.
- Semaglutide dosage calculator · Tirzepatide dosage calculator
- How long a reconstituted vial lasts — a different clock entirely: the vial, not the drug in you.