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Dosage information

Tirzepatide dosage

Tirzepatide has label dosing only as the prescription medicines Mounjaro and Zepbound, and the prescriber sets each dose.12 Both labels start at 2.5 mg under the skin once weekly and raise the dose in 2.5 mg steps after at least 4 weeks, to at most 15 mg weekly in adults.3456 No dose is established for research-labeled vials.7

This page summarizes published sources for information only. It is not medical advice and does not tell anyone to use a product. Questions about your own health belong with a licensed clinician. For questions about an order or a product, contact us.

How label dosing works

Tirzepatide is dosed once weekly under a prescriber's direction, within each label's schedule.12 Both labels start low and raise the dose step by step.34 Most nausea, vomiting and diarrhea in the trials happened during those increases and eased over time.8 The two brands share one active ingredient but have different approved uses, so their schedules differ after the first month.910

Mounjaro (type 2 diabetes)

  • Start: 2.5 mg injected under the skin once weekly.3
  • Increase: in 2.5 mg steps after at least 4 weeks on the current dose, if more blood sugar control is needed.3
  • Maximum: 15 mg once weekly in adults, and 10 mg once weekly in children 10 years and older.5

Zepbound (weight reduction and sleep apnea)

  • Start: 2.5 mg once weekly for 4 weeks.11 This dose starts treatment and is not approved for maintenance.11
  • Increase: to 5 mg after 4 weeks, then in 2.5 mg steps after at least 4 weeks on the current dose.4
  • Maintenance: 5, 10 or 15 mg once weekly for weight reduction, and 10 or 15 mg once weekly for obstructive sleep apnea.12
  • Maximum: 15 mg once weekly for all uses.6

Timing and missed doses

  • When: once weekly, at any time of day, with or without meals.13
  • Missed dose: the Mounjaro label says to give it within 4 days (96 hours).14 After that, the missed dose is skipped and the next one is given on the usual day.14
  • Changing the day: allowed when the two doses are at least 3 days (72 hours) apart.15
  • Steady levels: blood levels level off after 4 weeks of weekly doses, and the half-life is about 5 days.1617
  • Injection sites: the abdomen or thigh, or the back of the upper arm if another person gives the injection, rotating sites with each dose.13

Doses studied in trials

  • SURPASS-1 (40 weeks, 478 adults with type 2 diabetes): 5, 10 or 15 mg once weekly versus placebo.1819 HbA1c fell 1.87% to 2.07%.19
  • SURPASS-2 (40 weeks, 1,879 adults on metformin): 5, 10 or 15 mg once weekly versus semaglutide 1 mg.2021 HbA1c fell 2.01 to 2.30 points, versus 1.86 with semaglutide.21
  • SURPASS-CVOT (13,299 adults with type 2 diabetes and established cardiovascular disease): tirzepatide up to 15 mg once weekly versus dulaglutide 1.5 mg.22
  • SURPASS-PEDS (30 weeks, 99 patients aged 10 and older): 5 mg and 10 mg once weekly both lowered HbA1c more than placebo.2324
  • SURMOUNT-1 (72 weeks, 2,539 adults with obesity): 5, 10 or 15 mg once weekly, including a 20-week period of dose increases.2526 Average weight fell 15.0% at 5 mg, 19.5% at 10 mg and 20.9% at 15 mg.2728 Its three-year analysis followed 1,032 participants with prediabetes for 176 weeks.25
  • SURMOUNT-4 (670 adults randomized): after a 36-week open-label lead-in, participants continued tirzepatide or switched to placebo for 52 weeks.2930
  • SURMOUNT-OSA (two 52-week trials): doses were raised over up to 20 weeks to each person's maximum tolerated dose, 10 or 15 mg weekly.31
  • SURMOUNT-5 (72 weeks): tirzepatide at each person's maximum tolerated dose, 10 or 15 mg weekly, versus semaglutide.32
  • SURMOUNT-MAINTAIN (2026): after 60 weeks at 10 or 15 mg, one group stepped down to 5 mg weekly.33 At week 112, modeled average weight was 16.6% below baseline on 5 mg, 21.9% below on the full dose and 9.9% below on placebo.3435 The authors said a lower dose might be an alternative to stopping, though responses vary.36
  • Model estimate for 2.5 mg: the Mounjaro label's exposure-response model predicts that 2.5 mg weekly may lower HbA1c by about 1.8% and fasting glucose by about 43 mg/dL after 52 weeks.37 This is a model estimate, not a trial result.37

Doses in animal studies

A 2-year rat study injected tirzepatide under the skin twice weekly at 0.15, 0.50 or 1.5 mg/kg.38 Those doses gave 0.1 to 1 times the exposure of the 15 mg maximum human dose, and caused thyroid C-cell tumors.3839 A 6-month study in rasH2 mice used 1, 3 and 10 mg/kg twice weekly and found that tirzepatide did not cause tumors.40 These are animal study doses, listed to describe the research.

Research-labeled vials have no established dose

Approved dosing exists only for Mounjaro and Zepbound.12 Research-labeled tirzepatide has no approved FDA application, so no dose for any person is established for it.7 FDA says research-labeled GLP-1 products have been sold to consumers with dosing instructions, and calls them of unknown quality.41 It has received adverse event reports, some needing hospital care, that may be related to dosing errors when patients measured and self-injected compounded semaglutide.42 It has also received reports that may be related to compounded semaglutide or tirzepatide prescribed above the label dose.43 Nothing on this page is a dose for you. General background is in Peptide dosage basics.

Back to the Tirzepatide profile. Related: Tirzepatide side effects, Tirzepatide benefits and uses and How to reconstitute Tirzepatide.

More on Tirzepatide

  • Tirzepatide side effects

    Side effects of Tirzepatide as reported in labels, trials and published studies, with links to the full profile. Reviewed by a qualified reviewer.

  • Tirzepatide benefits and uses

    What published sources report about Tirzepatide and its uses, with the evidence level of each finding. No promises.

  • How to reconstitute Tirzepatide

    How Tirzepatide is reconstituted, the supplies used, and the calculator, step by step. Sourced and reviewed.

Frequently asked questions

How much tirzepatide to start with?

Under both FDA labels, the approved medicines start at 2.5 mg injected under the skin once weekly.311 For Zepbound, that dose lasts 4 weeks and is for starting treatment only, not for maintenance.11 The prescriber sets the dose and decides when to raise it. These are prescribing rules for Mounjaro and Zepbound; no starting dose is established for research-labeled vials.7

Can tirzepatide 2.5 mg help with weight loss?

The Zepbound label treats 2.5 mg as a starting dose that is not approved for maintenance.11 The main weight-loss trial, SURMOUNT-1, tested 5, 10 and 15 mg, not 2.5 mg.26 For type 2 diabetes, the Mounjaro label's model predicts that 2.5 mg weekly may lower HbA1c by about 1.8% after 52 weeks, but that is a model estimate and not a weight result.37

What happens if a weekly dose is missed?

The Mounjaro label says a missed dose should be given as soon as possible within 4 days (96 hours).14 If more than 4 days have passed, the missed dose is skipped and the next one is given on the usual day.14 The weekly day can be changed if the two doses are at least 3 days (72 hours) apart.15 The prescriber can advise on a specific case.

What is the maximum dose of tirzepatide?

Both labels cap the dose at 15 mg once weekly for adults.56 For children 10 years and older with type 2 diabetes, the Mounjaro maximum is 10 mg once weekly.5 Doses rise in 2.5 mg steps no sooner than every 4 weeks, and the main weight-loss trial used 20 weeks of increases to reach its highest dose.426

Is there a dose for research-labeled tirzepatide?

No. Approved dosing exists only for Mounjaro and Zepbound, which are prescription medicines.12 Research-labeled tirzepatide has no approved FDA application, and FDA describes such products sold to consumers as of unknown quality.741 Trial and animal doses on this page describe what was studied. They are not guidance for any person.

Written by D2C Peptides Editorial Team.

Pending qualified review.

Updated .

Sources

  1. Drugs@FDA: NDA 215866 (MOUNJARO), sponsor and marketing status. U.S. Food and Drug Administration, 2026.
  2. Drugs@FDA: NDA 217806 (ZEPBOUND), marketing status. U.S. Food and Drug Administration, 2026.
  3. MOUNJARO Prescribing Information, revised 08/2026: Recommended dosage. U.S. Food and Drug Administration (label for Eli Lilly and Company), 2026.
  4. ZEPBOUND Prescribing Information, revised 08/2026: Dose escalation. U.S. Food and Drug Administration (label for Eli Lilly and Company), 2026.
  5. Same source as 3: Maximum dosage.
  6. Same source as 4: Maximum dosage.
  7. FDA Warning Letter: Gram Peptides, March 31, 2026 (no approved application). U.S. Food and Drug Administration, CDER, 2026.
  8. Same source as 3: Gastrointestinal adverse reactions (timing).
  9. Same source as 3: MOUNJARO (tirzepatide) US Prescribing Information, revised 08/2026: Indications (type 2 diabetes).
  10. Same source as 4: ZEPBOUND (tirzepatide) US Prescribing Information, revised 08/2026: Indications (weight).
  11. Same source as 4: Starting dosage.
  12. Same source as 4: Maintenance dosage.
  13. Same source as 3: Administration timing.
  14. Same source as 3: Missed doses.
  15. Same source as 3: Changing the dosing day.
  16. Same source as 3: Steady state.
  17. Same source as 3: Elimination.
  18. Same source as 3: SURPASS-1 design.
  19. Efficacy and safety of a novel dual GIP and GLP-1 receptor agonist tirzepatide in patients with type 2 diabetes (SURPASS-1), PMID 34186022. The Lancet (via NLM PubMed E-utilities), 2021.
  20. Same source as 3: SURPASS-2 design.
  21. Tirzepatide versus Semaglutide Once Weekly in Patients with Type 2 Diabetes (SURPASS-2), PMID 34170647. New England Journal of Medicine (via NLM PubMed E-utilities), 2021.
  22. Same source as 3: SURPASS-CVOT design.
  23. Same source as 3: Pediatric trial design.
  24. Same source as 3: SURPASS-PEDS results.
  25. Tirzepatide for Obesity Treatment and Diabetes Prevention (SURMOUNT-1, 3 years), PMID 39536238: methods. New England Journal of Medicine (via NLM PubMed E-utilities), 2025.
  26. Tirzepatide Once Weekly for the Treatment of Obesity (SURMOUNT-1), PMID 35658024: methods. New England Journal of Medicine (via NLM PubMed E-utilities), 2022.
  27. Same source as 26: SURMOUNT-1 abstract: weight change at 5 mg and 10 mg (PMID 35658024).
  28. Same source as 26: SURMOUNT-1 abstract: weight change at 15 mg and placebo (PMID 35658024).
  29. Continued Treatment With Tirzepatide for Maintenance of Weight Reduction in Adults With Obesity (SURMOUNT-4), PMID 38078870: lead-in. JAMA (via NLM PubMed E-utilities), 2024.
  30. Same source as 29: SURMOUNT-4 abstract: randomized withdrawal results (PMID 38078870).
  31. Same source as 4: Sleep apnea study dosing.
  32. SURMOUNT-5 abstract: methods (PMID 40353578). New England Journal of Medicine (via NLM PubMed E-utilities), 2025.
  33. SURMOUNT-MAINTAIN abstract: randomization (PMID 42119587). The Lancet (via NLM PubMed E-utilities), 2026.
  34. Same source as 33: Tirzepatide for maintenance of bodyweight reduction in people with obesity in the USA (SURMOUNT-MAINTAIN), PMID 42119587: maximum tolerated dose arm.
  35. Same source as 33: 5 mg and placebo arms (PMID 42119587).
  36. Same source as 33: interpretation (PMID 42119587).
  37. Same source as 3: Exposure-response.
  38. Same source as 3: Rat carcinogenicity study.
  39. Same source as 3: Boxed warning.
  40. Same source as 3: Mouse carcinogenicity study.
  41. FDA's Concerns with Unapproved GLP-1 Drugs Used for Weight Loss: consumer warning. U.S. Food and Drug Administration, 2026.
  42. Same source as 41: dosing errors.
  43. Same source as 41: doses above the label.