Mounjaro and Metformin: Is It Safe? Label, Studies
Commonly used together; Mounjaro was tested alongside metformin in its trials.
- Verdict
- Generally fine together
- Label names it
- No
- General caution
- Pills absorbed more slowly
Check a GLP-1 interaction
Key facts about Mounjaro
About 5 days is the half-life. After 5 d, half is gone; about 3% remains after five half-lives (25 d).
In SURPASS-1, a 40-week study of type 2 diabetes, people lost 7.8 kg. The placebo group lost 1 kg.
In US dollars, monthly prices include the list price and self-pay offers. Both come from the maker's price page.
Sources: FDA label (DailyMed), healthsystemtracker.org, pricinginfo.lilly.com.
Mounjaro and metformin: the verdict
Generally fine together
Word for word from the drug interactions section of the Mounjaro label:
“MOUNJARO delays gastric emptying and thereby has the potential to impact the absorption of concomitantly administered oral medications. Caution should be exercised when oral medications”
Source: FDA label (DailyMed).
Details from the Mounjaro label
The Mounjaro label does not include Metformin anywhere. Those lines in the label still apply to Metformin.
| Named in the label | The risk | What the label tells doctors |
|---|---|---|
| Insulin or sulfonylureas | Low blood sugar | Using this medicine with insulin or a sulfonylurea, such as glipizide or glimepiride, raises the chance of low blood sugar levels. |
| Oral medicines | Pills absorbed differently | Because it slows stomach emptying, the absorption of other pills may also change. |
Source: Mounjaro label (DailyMed).
What the studies show
- use with metformin studied in clinical trials
Source: FDA label (DailyMed).
The practical rule
- Continue both medicines as prescribed, and contact your doctor if stomach upset continues.
- Tell whoever prescribes your GLP-1 medicine about every pill you use, including this pill.
- Ask your pharmacist if any of your pills need a steady blood level. You may need checks for those pills when you begin treatment or raise the dose.
- Check your blood sugar more often during the first weeks and any time the dose goes up.
Source: FDA label (DailyMed).
Metformin with other GLP-1s
None of the 10 GLP-1 labels lists Metformin in its drug interaction section. All labels share a general caution about swallowed pills, so the answer remains the same for the entire class.
This same question also applies to Ozempic, Wegovy, Rybelsus, Zepbound, Trulicity.
Source: FDA label (DailyMed).