Mounjaro Long-Term Side Effects: What Years of Data Show
Mounjaro has been sold in the US since 2022. The long-term label warnings are thyroid C-cell tumors (seen in rodents), pancreatitis, gallbladder disease and kidney injury from fluid loss.
- Sold in the US since
- 2022
- Most common
- Nausea 18%
- Same on placebo
- 4%
- Trial group
- Adults with type 2 diabetes
A quick look at Mounjaro
Its half-life is about 5 days: after 5 d, half is gone, and after five half-lives (25 d), about 3% remains.
In the 40-week SURPASS-1 trial for type 2 diabetes, weight loss was 7.8 kg, compared with 1 kg on placebo.
Monthly US dollar prices include the list price and self-pay offers, all taken from the maker's price page.
Sources: FDA label (DailyMed), healthsystemtracker.org, pricinginfo.lilly.com.
Serious warnings, in plain words
- A boxed warning covers Thyroid C-cell tumors. It led to thyroid C-cell tumors in rodents. Whether it does the same in people is not known. If you or a family member has had medullary thyroid cancer (MTC), do not use it. It is also not for people with MEN 2.
- Pancreatitis. Pancreatitis: It can lead to inflammation in the pancreas. Get care and stop taking it if severe stomach pain continues and sometimes reaches your back.
- Low blood sugar. Low blood sugar is more likely when you use it with insulin or a sulfonylurea, and those medicines may need lower doses.
- Serious allergic reactions. Reports include serious allergic reactions, with swelling of the lips, throat, or face. If they happen, stop taking it and get help right away.
- Kidney injury due to fluid loss. Vomiting or diarrhea can cause fluid loss, which can lead to kidney injury. Report heavy fluid loss and drink fluids.
- Reactions affecting the stomach and gut can be severe. Stomach and gut side effects are common and can be severe. This product is not recommended for people with severe gastroparesis.
- Diabetic eye disease may get worse. Those with type 2 diabetes may find that diabetic eye disease worsens, especially if blood sugar falls quickly. Eye checks are important if you already have diabetic eye disease.
- Gallbladder disease. Both gallstones and gallbladder inflammation are possible. Report fever, yellow skin or eyes, or belly pain in the upper right area.
- Food entering the lungs during anesthesia or sedation. Food can stay in the stomach longer, which matters during anesthesia or deep sedation. Tell your care team before you have any procedure.
Source: FDA label (DailyMed).
Source: FDA label (DailyMed).
Mounjaro long term side effects: label rates vs placebo
The FDA label lists 7 common Mounjaro side effects found in placebo-controlled trials. In the final column, you can see the amount by which each side effect appeared more often than with placebo.
| Side effect | Placebo | Mounjaro 5 mg | Mounjaro 10 mg | Mounjaro 15 mg | More than placebo, 15 mg |
|---|---|---|---|---|---|
| Nausea | 4% | 12% | 15% | 18% | +14 points |
| Diarrhea | 9% | 12% | 13% | 17% | +8 points |
| Decreased Appetite | 1% | 5% | 10% | 11% | +10 points |
| Vomiting | 2% | 5% | 5% | 9% | +7 points |
| Dyspepsia | 3% | 8% | 8% | 5% | +2 points |
| Constipation | 1% | 6% | 6% | 7% | +6 points |
| Abdominal Pain | 4% | 6% | 5% | 5% | +1 points |
Source: FDA label (DailyMed).