Tirzepatide half-life: how long does it stay in the body?

What is the half-life of tirzepatide?

Tirzepatide has an elimination half-life of approximately 5 days in the US prescribing label for Mounjaro, a summary of pharmacokinetic data from trial participants, whose number the label does not state, that does not describe any one person (US Mounjaro label, DailyMed, version published 2 September 2026). A half-life is the time the blood level takes to fall by half. The TGA's assessment report for Mounjaro gives model-based population estimates of a mean terminal half-life of 5.4 days in people with type 2 diabetes and 5.7 days in people with obesity or overweight, fitted to human trial data whose participant count is not supplied in that summary, not individual measurements (TGA AusPAR, finalised 20 September 2024). The first-in-human Phase 1 trial, funded by the maker of tirzepatide, reported a mean half-life of approximately 5 days, or 116.7 hours, in a paper whose single-exposure table covers cohorts of 5 to 12 healthy volunteers, and the result does not cover people with other conditions (Coskun et al., Molecular Metabolism, 2018).

After one half-life, about half of the measured amount is left. After two, about a quarter. These fractions define half-life; they do not measure a person's blood level.

In the six single-exposure cohorts of the first-in-human study, which enrolled 5 to 12 healthy volunteers each, geometric mean half-lives ran from 106 to 124 hours, so that study does not describe people with other conditions (Coskun et al., Molecular Metabolism, 2018). The tirzepatide research guide covers what the compound is; this page covers what the body does to it.

What is the half-life of Mounjaro?

Mounjaro has the same half-life as tirzepatide, approximately 5 days, because Mounjaro is the brand name of an approved tirzepatide medicine; the figure is a group summary from trial participants, whose number the label does not state, and not a value for any one person (US Mounjaro label, DailyMed, 2 September 2026). The US label for Zepbound, a second tirzepatide brand, gives approximately 5 to 6 days in patients with overweight or obesity and in patients with sleep apnoea and obesity, a human group estimate with no participant count supplied, not an individual value (US Zepbound label, DailyMed, 2 September 2026). The TGA register lists Mounjaro entries dated 23 December 2022 (type 2 diabetes), 10 September 2024 (chronic weight management) and 2 June 2025 (moderate to severe obstructive sleep apnoea in adults with obesity), read 14 October 2026. A brand name changes the label, not the molecule.

The label figure and the report figures are separate records from separate documents, and this page does not rank them.

What is the half-life of Wegovy?

Wegovy has an elimination half-life of approximately 1 week in its US label, a group figure from trial participants whose number the label does not state, so it does not describe any one person (DailyMed, version published 30 June 2026). From that half-life, the same label states that semaglutide will be present in the circulation for about 5 to 7 weeks after the final study exposure, a group figure with no participant number stated and not a prediction for any one person (US Wegovy label, DailyMed, 30 June 2026). The US Ozempic label gives approximately 1 week and about 5 weeks after the final study exposure, estimates from human label data with no participant count supplied, not individual values (US Ozempic label, DailyMed, published 10 June 2026). Wegovy and Ozempic are two brands of one molecule, semaglutide.

On label figures, tirzepatide's half-life of about 5 days (US Mounjaro label, DailyMed, 2 September 2026) is shorter than semaglutide's of about 1 week (US Wegovy label, DailyMed, 30 June 2026), and neither label states how many trial participants the figure summarises, so each is a group figure and not a prediction for any one person. The figures come from separate trial programmes. The PubMed records and Mounjaro, Ozempic and Wegovy label sections searched for this page on 14 October 2026 did not identify a head-to-head pharmacokinetic study; that bounded search does not establish that no such study exists.

When does semaglutide reach its peak blood level?

Semaglutide reaches its maximum blood concentration 1 to 3 days after exposure in the non-oral formulation data of the US Ozempic and US Wegovy labels, which are group figures from trial participants, with no participant number stated, and not values for any one person (US Ozempic label, DailyMed, 10 June 2026; US Wegovy label, DailyMed, 30 June 2026). Those figures exclude oral formulation data. In the same non-oral formulation data, the labels give an absolute bioavailability of 89%, meaning that 89% of the studied amount reaches the blood, again a group figure from trial participants with no number stated not an individual measurement and excluding oral formulation data (US Ozempic label, DailyMed, 10 June 2026; US Wegovy label, DailyMed, 30 June 2026). Peak timing answers a different question from half-life: the peak says when the level is highest, and the half-life says how fast it falls afterwards.

Time to peak and half-life describe different parts of the same blood-level curve. A level that rises to a peak and then falls by half over a set time has a rising and a falling side, and the two measures describe those two sides.

When does tirzepatide reach its peak blood level?

Tirzepatide reaches its maximum blood concentration 8 to 72 hours after exposure in the pharmacokinetic data of the US Mounjaro label, a group range from trial participants, with no participant number stated, that does not describe any one person (DailyMed, 2 September 2026). The TGA's 2024 assessment report gives a median of about 24 hours within that range, from human trial data for which the passage read for this page gives no participant number, as a group median and not a prediction for any one person (TGA AusPAR, 20 September 2024). The label reports a mean absolute bioavailability of 80%, a group figure from trial participants with no number stated and not a value for any one person (US Mounjaro label, DailyMed, 2 September 2026). In the six single-exposure cohorts of 5 to 12 healthy volunteers each in the first-in-human trial, funded by the maker of tirzepatide, the median time to peak ran from 24 to 48 hours, and that trial does not cover people with other conditions (Coskun et al., Molecular Metabolism, 2018).

The label's range of 8 to 72 hours, from human trial data in the US Mounjaro label (DailyMed, 2 September 2026), shows that times to peak differed widely in the data behind it, and the label does not say how many participants fell at each end. Tirzepatide side effects records the adverse events that trials report.

How long does it take for tirzepatide to leave the body?

The US Mounjaro and Zepbound labels (DailyMed, 2 September 2026) give a half-life and give no time to full clearance, as checked for this page on 14 October 2026. Arithmetic from the approximately 5-day group half-life in the US Mounjaro label (DailyMed, 2 September 2026) leaves about 3% of a measured amount after five half-lives, roughly 25 days; that figure is a calculation and not a published measurement in any person, and it is not a prediction for an individual. For semaglutide the label does state a time: present in the circulation for about 5 to 7 weeks after the final study exposure, a group figure derived from the label's half-life, from trial participants with no participant number stated, and not a prediction for any one person (US Wegovy label, DailyMed, 30 June 2026).

The US Mounjaro label describes the body breaking tirzepatide down by proteolytic cleavage of the peptide backbone (the body's ordinary protein-cutting enzymes), beta-oxidation of the fatty diacid, and amide hydrolysis. The label names urine and faeces as the primary excretion routes of the breakdown products, and it does not state the study model or participant number behind that statement (US Mounjaro label, DailyMed, 2 September 2026).

Five half-lives is a convention, not a cliff. A falling level does not suddenly reach zero at that point. The arithmetic describes an ideal curve, not a person's clearance time.

Why does tirzepatide stay in the blood for days?

Tirzepatide stays in the blood for days because a C20 fatty diacid attached to the peptide binds albumin, the main carrier protein in blood, and the US Mounjaro label states that the fatty diacid enables albumin binding and prolongs the half-life (US Mounjaro label, DailyMed, 2 September 2026; Coskun et al., Molecular Metabolism, 2018). The label does not state the study model or participant number behind that statement, and this page repeats no binding percentage for that reason. Semaglutide uses the same design idea, with a C18 fatty di-acid attached at lysine 26 (US Ozempic label, DailyMed, 10 June 2026; Lau et al., Journal of Medicinal Chemistry, 2015).

Picture albumin as a slow, wide river that carries fatty acids from place to place. A peptide with a fatty-acid tail slips into that current and drifts along with it, instead of being filtered out in the first rush. Where tirzepatide comes from explains the design of that tail.

Lau et al.'s 2015 Journal of Medicinal Chemistry paper reports semaglutide plasma half-life in mini-pigs, with no animal count in the abstract; this animal result does not establish a human result.

Evidence limits

What do the half-life figures not show?

The US Mounjaro label also reports an apparent population mean clearance of 0.061 L/h and a mean apparent volume of distribution of about 10.3 L in people with type 2 diabetes, model estimates from trial data, with no participant number stated, and not measurements in each person (US Mounjaro label, DailyMed, 2 September 2026). The TGA's report bases its clearance estimate of 0.0606 L/h on human population pharmacokinetic parameters, which are fitted estimates and not measurements in each person, and the passage read for this page gives no participant number (TGA AusPAR, 20 September 2024). How long retatrutide stays in the blood is a separate record for a different compound.

Is research-use tirzepatide the same material the labels describe?

No. Every half-life figure on this page was measured on a tirzepatide medicine or trial drug product, given to enrolled participants under clinical trial conditions or regulatory review (US labels; TGA AusPAR; Coskun et al., Molecular Metabolism, 2018). Research-use tirzepatide is a laboratory compound. Research material is not a medicine, is not a substitute for one, and is not for human or animal use. The published numbers describe what happened in those studies and say nothing about any material outside them.

What exists for laboratory work is reference material with paperwork. The catalogue lists tirzepatide reference material as freeze-dried laboratory stock. Current certification for that material is unverified, and nothing on this page describes it.