Guides · PeptideU · 9 min read

What Is Mounjaro Approved For? Label Indications, Per the Research

The short answer

Mounjaro (tirzepatide) is a prescription medicine. In the United States, the Mounjaro label covers one approved indication: an adjunct to diet and exercise to improve glycaemic control in adults with type 2 diabetes, approved by the FDA in May 2022. In several other regions the Mounjaro label also covers chronic weight management, and in the United States tirzepatide is marketed under a separate brand for weight management and obstructive sleep apnoea. Other uses discussed in the literature remain investigational.

Mounjaro (tirzepatide) is a prescription medicine. In the United States, the Mounjaro-branded label carries a single approved indication: as an adjunct to diet and exercise to improve glycaemic control in adults with type 2 diabetes mellitus. The US Food and Drug Administration granted that approval in May 2022. Tirzepatide — the active molecule in Mounjaro — also holds approvals for chronic weight management and for obstructive sleep apnoea in adults with obesity, but in the United States those indications sit on a separately branded tirzepatide product rather than on the Mounjaro label. Outside the United States, several regulators have placed weight-management wording on the Mounjaro label itself. Labelling differs by country and changes over time, and only a prescribing clinician can say what applies to an individual.

This page is for educational purposes only and is not medical advice; consult a licensed physician or other qualified prescriber about any medicine, including Mounjaro. It summarises what regulatory labelling and the published pivotal-trial literature report, and it does not provide dosing or prescribing guidance.

What Mounjaro Is: A Dual GIP/GLP-1 Receptor Agonist

Tirzepatide is a once-weekly injectable peptide that activates both the glucose-dependent insulinotropic polypeptide (GIP) receptor and the glucagon-like peptide-1 (GLP-1) receptor. A 2022 review in Cardiovascular Diabetology described tirzepatide as a dual GIP/GLP-1 receptor co-agonist developed for type 2 diabetes and reported that the phase 3 programme produced large reductions in both HbA1c and body weight (PMID 36050763). That dual-receptor mechanism is the pharmacological basis for the indications described below.

Approved Indications at a Glance

Indication	Brand carrying it	Regulator and date
Adjunct to diet and exercise to improve glycaemic control in adults with type 2 diabetes	Mounjaro	US FDA, May 2022
Chronic weight management in adults with obesity or overweight with a weight-related comorbidity, alongside diet and physical activity	Zepbound (US tirzepatide brand); Mounjaro label in several other regions	US FDA, November 2023
Moderate-to-severe obstructive sleep apnoea in adults with obesity, alongside a reduced-calorie diet and increased physical activity	Zepbound (US tirzepatide brand)	US FDA, December 2024

Readers comparing labels across countries should note that the same molecule can appear under different brand names and with differently worded indications. Regional labelling is the authoritative source in each jurisdiction.

Type 2 diabetes: the original Mounjaro indication

The diabetes indication rests on the SURPASS phase 3 programme. In SURPASS-2, an open-label randomised trial, participants with type 2 diabetes received tirzepatide 5 mg, 10 mg or 15 mg once weekly or semaglutide 1 mg once weekly, and the researchers reported mean HbA1c reductions of 2.01, 2.24 and 2.30 percentage points with tirzepatide versus 1.86 with semaglutide at 40 weeks (PMID 34170647). The study also reported greater mean body-weight reduction across the tirzepatide groups than with semaglutide 1 mg (PMID 34170647).

Regional evidence supported approvals elsewhere. SURPASS J-mono, a double-blind randomised phase 3 trial in Japanese adults with type 2 diabetes, compared tirzepatide monotherapy with dulaglutide and reported greater HbA1c and body-weight reductions with tirzepatide across the doses studied (PMID 35914543).

Chronic weight management

The weight-management indication rests on the SURMOUNT programme. SURMOUNT-1 randomised adults with obesity, or overweight with at least one weight-related complication and without diabetes, to once-weekly tirzepatide 5 mg, 10 mg or 15 mg or placebo for 72 weeks; the researchers reported mean weight reductions of 15.0%, 19.5% and 20.9% with tirzepatide versus 3.1% with placebo (PMID 35658024).

SURMOUNT-2 extended the question to adults who had both obesity and type 2 diabetes. In that double-blind, placebo-controlled phase 3 trial, the study reported mean weight reductions of 12.8% with tirzepatide 10 mg and 14.7% with 15 mg at 72 weeks, compared with 3.2% on placebo (PMID 37385275).

SURMOUNT-4 examined what happened when treatment was continued or withdrawn. After a 36-week open-label lead-in, participants were re-randomised to continue tirzepatide or switch to placebo, and the researchers reported further weight reduction during continued treatment versus substantial weight regain after the switch to placebo over the following 52 weeks (PMID 38078870). A 2025 review in Expert Opinion on Pharmacotherapy summarised the SURMOUNT evidence base for overweight and obesity management and described tirzepatide's efficacy and tolerability profile across those trials (PMID 39632534).

Obstructive sleep apnoea in adults with obesity

The sleep-apnoea indication rests on the SURMOUNT-OSA trials. Those phase 3 trials randomised adults with moderate-to-severe obstructive sleep apnoea and obesity — one trial in participants not using positive airway pressure, one in participants using it — to tirzepatide or placebo for 52 weeks, and the researchers reported significantly greater reductions in the apnoea–hypopnoea index with tirzepatide than with placebo in both trials, alongside greater body-weight reduction (PMID 38912654). The trial publication framed tirzepatide as an addition to a reduced-calorie diet and increased physical activity rather than as a replacement for existing sleep-apnoea care (PMID 38912654).

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What Is Not an Approved Indication

Several other uses appear in the tirzepatide literature. They are investigational or off-label; none of them is an approved indication on any tirzepatide label, and publication of a positive trial result is not the same as a regulatory approval.

Diabetes prevention in prediabetes

A 2025 New England Journal of Medicine report of the 176-week SURMOUNT-1 extension in adults with obesity and prediabetes reported markedly lower progression to type 2 diabetes with tirzepatide than with placebo, with weight reduction sustained over three years (PMID 39536238). The researchers also reported weight regain after treatment discontinuation during the off-treatment follow-up period (PMID 39536238). Diabetes prevention is not a labelled indication.

Liver fat and metabolic dysfunction-associated steatotic liver disease

The SURPASS-3 MRI substudy compared tirzepatide with insulin degludec in people with type 2 diabetes and reported significantly greater reductions in liver fat content and in visceral and abdominal subcutaneous adipose tissue with tirzepatide (PMID 35468325). The 2024 EASL–EASD–EASO clinical practice guidelines on metabolic dysfunction-associated steatotic liver disease discussed incretin-based therapies within the broader management of MASLD and emphasised weight management and cardiometabolic risk reduction (PMID 38851997). Liver disease is not a labelled tirzepatide indication.

Body composition and muscle mass

A 2025 post-hoc analysis of SURPASS-3 MRI examined muscle composition in people with type 2 diabetes treated with tirzepatide and reported changes in muscle volume and muscle fat infiltration alongside the fat-mass changes seen in the parent trial (PMID 40318682). Post-hoc analyses are hypothesis-generating and do not create or extend an indication.

Adverse Events in the Trials: What Studies Report

Across the pivotal programme, gastrointestinal events dominated the safety reporting. SURMOUNT-1 reported nausea, diarrhoea, constipation and vomiting as the most common adverse events with tirzepatide, mostly mild to moderate and occurring primarily during dose escalation (PMID 35658024). SURPASS-2 similarly reported that the most frequent adverse events with tirzepatide were gastrointestinal and mostly mild to moderate, with discontinuation due to adverse events occurring in a minority of participants (PMID 34170647).

In SURMOUNT-2, conducted in adults with obesity and type 2 diabetes, the researchers reported gastrointestinal adverse events as the most common, again mainly mild to moderate in severity (PMID 37385275). SURMOUNT-OSA reported that the most frequently reported adverse events with tirzepatide were gastrointestinal (PMID 38912654), and the 2025 review of tirzepatide for overweight and obesity summarised a comparable tolerability pattern across the SURMOUNT trials (PMID 39632534). Full contraindications, warnings and precautions — including boxed warnings — are set out in regional prescribing information and are assessed by a prescribing clinician for each individual.

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Why Brand Names and Indications Differ by Country

Regulatory agencies approve a specific product under a specific brand for specific wording. In the United States, the FDA approved Mounjaro for type 2 diabetes in May 2022 and subsequently approved tirzepatide for chronic weight management (November 2023) and for moderate-to-severe obstructive sleep apnoea in adults with obesity (December 2024) under the separate Zepbound brand. Other regulators, including those in Europe and the United Kingdom, have placed both glycaemic-control and weight-management wording on the Mounjaro label. Because of this, a statement such as "Mounjaro is approved for weight loss" can be accurate in one country and inaccurate in another. The current local prescribing information is the authoritative source.

Reading the Evidence Carefully

Approved indication ≠ every studied outcome. Trials such as the SURPASS-3 MRI substudy reported liver-fat and adipose-tissue outcomes (PMID 35468325), but those outcomes did not become label indications.
Trial populations are specific. SURMOUNT-1 enrolled adults without diabetes (PMID 35658024), while SURMOUNT-2 enrolled adults with type 2 diabetes (PMID 37385275), and results are not automatically interchangeable.
Durability was studied directly. SURMOUNT-4 reported weight regain after randomised withdrawal of tirzepatide (PMID 38078870), and the three-year SURMOUNT-1 report described a similar pattern after discontinuation (PMID 39536238).
Comparators matter. SURPASS-2 compared tirzepatide with semaglutide 1 mg, not with higher semaglutide doses studied in other programmes (PMID 34170647).

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Questions a Prescribing Clinician Can Answer

Decisions about whether a medicine is appropriate, which brand and indication apply locally, how it interacts with other conditions and medicines, and how it is monitored are clinical judgements. A licensed physician or other qualified prescriber is the right source for those questions; this page describes published findings and regulatory status only.

References

Frequently asked questions

Is Mounjaro FDA approved?▾

Yes. The FDA approved Mounjaro (tirzepatide) in May 2022 as an adjunct to diet and exercise to improve glycaemic control in adults with type 2 diabetes. That approval followed the SURPASS phase 3 programme, including a trial that reported larger HbA1c reductions with tirzepatide 5, 10 and 15 mg than with semaglutide 1 mg over 40 weeks (PMID 34170647).

Is Mounjaro approved for weight loss?▾

In the United States, chronic weight management sits on a separately branded tirzepatide product approved in November 2023, not on the Mounjaro label; several other regulators include weight-management wording on the Mounjaro label itself. The supporting trial reported mean weight reductions of 15.0%, 19.5% and 20.9% with tirzepatide 5, 10 and 15 mg over 72 weeks versus 3.1% with placebo (PMID 35658024).

What is the newest tirzepatide indication?▾

Moderate-to-severe obstructive sleep apnoea in adults with obesity, approved in the United States in December 2024 under the separate tirzepatide brand. In the SURMOUNT-OSA phase 3 trials, researchers reported significantly greater reductions in the apnoea–hypopnoea index over 52 weeks with tirzepatide than with placebo, alongside greater body-weight reduction (PMID 38912654).

Is tirzepatide approved to prevent type 2 diabetes?▾

No. Diabetes prevention is not a labelled indication. A 2025 report of the 176-week SURMOUNT-1 extension in adults with obesity and prediabetes reported substantially lower progression to type 2 diabetes with tirzepatide than with placebo, with weight regain observed after discontinuation during off-treatment follow-up (PMID 39536238). A prescribing clinician interprets such findings for an individual.

Is Mounjaro approved for fatty liver disease?▾

No. Liver disease is not an approved tirzepatide indication. The SURPASS-3 MRI substudy reported greater reductions in liver fat content and abdominal adipose tissue with tirzepatide than with insulin degludec in people with type 2 diabetes (PMID 35468325), and the 2024 EASL–EASD–EASO MASLD guidelines discussed incretin-based therapy within wider cardiometabolic management (PMID 38851997).

What adverse events did the pivotal trials report?▾

Gastrointestinal events predominated. SURMOUNT-1 reported nausea, diarrhoea, constipation and vomiting as the most common adverse events, mostly mild to moderate and concentrated during dose escalation (PMID 35658024). SURMOUNT-2 reported a similar pattern in adults with obesity and type 2 diabetes (PMID 37385275). Full warnings and contraindications appear in regional prescribing information and are assessed by a prescriber.

Does stopping tirzepatide change the trial results?▾

The literature studied this directly. SURMOUNT-4 re-randomised participants after a 36-week lead-in and reported continued weight reduction with ongoing tirzepatide versus substantial regain after switching to placebo (PMID 38078870). The three-year SURMOUNT-1 report described weight regain after discontinuation as well (PMID 39536238). Treatment duration decisions belong to a prescribing clinician.

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References

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18+ · Educational purposes only
This page summarises published research for education — it is not medical advice, and nothing here is a recommendation to use, purchase, or dose any substance. Study parameters described are what researchers reported, not instructions. Consult a qualified clinician before any health decision.