Mounjaro side effects: every rate on the FDA label
The most common adverse reactions, reported in ≥5% of patients treated with MOUNJARO are nausea, diarrhea, decreased appetite, vomiting, constipation, dyspepsia, and abdominal pain. (6.1) dailymed.nlm.nih.gov, Sep 27, 2026
Mounjaro is labeled for type 2 diabetes; these rates come from diabetes trials.
Boxed warning
WARNING: RISK OF THYROID C-CELL TUMORS
dailymed.nlm.nih.gov, Sep 27, 2026In both male and female rats, tirzepatide causes dose-dependent and treatment-duration-dependent thyroid C-cell tumors at clinically relevant exposures.
dailymed.nlm.nih.gov, Sep 27, 2026
How often each side effect happened
| Side effect | Placebo | 5 mg | 10 mg | 15 mg |
|---|---|---|---|---|
| Nausea | 4% | 12% | 15% | 18% |
| Diarrhea | 9% | 12% | 13% | 17% |
| Decreased Appetite | 1% | 5% | 10% | 11% |
| Vomiting | 2% | 5% | 5% | 9% |
| Constipation | 1% | 6% | 6% | 7% |
| Dyspepsia | 3% | 8% | 8% | 5% |
| Abdominal Pain | 4% | 6% | 5% | 5% |
Percent of people in the trial who reported it. Placebo is the comparison group.
The following gastrointestinal adverse reactions were reported more frequently in MOUNJARO-treated adult patients than placebo-treated patients (frequencies listed, respectively, as: placebo; 5 mg; 10 mg; 15 mg): eructation (0.4%, 3.0%, 2.5%, 3.3%), flatulence (0%, 1.3%, 2.5%, 2.9%), gastroesophageal reflux disease (0.4%, 1.7%, 2.5%, 1.7%), abdominal distension (0.4%, 0.4%, 2.9%, 0.8%).
dailymed.nlm.nih.gov, Sep 27, 2026- Injection site reactions 3.2% vs 0.4% placebo.
In the pool of placebo-controlled trials in adults, injection site reactions were reported in 3.2% of MOUNJARO-treated patients compared to 0.4% of placebo-treated patients.
dailymed.nlm.nih.gov, Sep 27, 2026 - CV outcomes trial exceptions incl. fatigue 10%.
In a CV outcomes trial of 6,647 adults with type 2 diabetes mellitus and established CV disease exposed to MOUNJARO, adverse reactions reported with MOUNJARO were similar with the exception of dysesthesia (0.7%), decreased appetite (17%), constipation (13%), vomiting (12%), abdominal pain (10%), and fatigue (10%) [see Clinical Studies (14.6)].
dailymed.nlm.nih.gov, Sep 27, 2026
Who stopped because of side effects
- GI-related discontinuation: 3.0% / 5.4% / 6.6% vs 0.4% placebo.
More patients receiving MOUNJARO 5 mg (3.0%), MOUNJARO 10 mg (5.4%), and MOUNJARO 15 mg (6.6%) discontinued treatment due to gastrointestinal adverse reactions than patients receiving placebo (0.4%).
dailymed.nlm.nih.gov, Sep 27, 2026
Who should not take it, pregnancy and breastfeeding
- Contraindicated with personal/family history of MTC or MEN 2.
A personal or family history of medullary thyroid carcinoma (MTC) or in patients with Multiple Endocrine Neoplasia syndrome type 2 (MEN 2) [see Warnings and Precautions (5.1)].
dailymed.nlm.nih.gov, Sep 27, 2026 - Contraindicated with known serious hypersensitivity to tirzepatide or excipients.
Known serious hypersensitivity to tirzepatide or any of the excipients in MOUNJARO. Serious hypersensitivity reactions, including anaphylaxis and angioedema, have been reported with MOUNJARO [see Warnings and Precautions (5.4)].
dailymed.nlm.nih.gov, Sep 27, 2026 - Use in pregnancy only if benefit justifies risk.
MOUNJARO should be used during pregnancy only if the potential benefit justifies the potential risk to the fetus.
dailymed.nlm.nih.gov, Sep 27, 2026 Pregnancy: Based on animal studies, may cause fetal harm. (8.1)
dailymed.nlm.nih.gov, Sep 27, 2026- Tirzepatide in breast milk undetectable or low (single-dose study).
In a single-dose clinical lactation study, the concentration of tirzepatide in breast milk was found to be either undetectable or low compared to the maternal administered dose (see Data).
dailymed.nlm.nih.gov, Sep 27, 2026
Label revised 8/2026: read the full label on DailyMed. The label lists more reactions and warnings than this page.
Doses and schedule: Mounjaro dosing · Price: Mounjaro cost · All medications: side effects compared
This page reports what the label says; it is not medical advice. Tell your prescriber about any side effect.Medical disclaimer.