Mounjaro vs Wegovy: Weight Loss, Side Effects, Price
Mounjaro (tirzepatide) and Wegovy (semaglutide) are both GLP-1 medicines, weekly injection versus weekly injection or daily tablet. Wegovy self-pay starts at $149 per month.
Mounjaro and Wegovy: a quick overview
Mounjaro and Wegovy compared side by side
| Mounjaro | Wegovy | |
|---|---|---|
| Medicine | Mounjaro |  Wegovy |
| Active ingredient | tirzepatide | semaglutide |
| Manufacturer | Eli Lilly | Novo Nordisk |
| How it is taken | Weekly injection | Weekly injection or daily tablet |
| Approved for | Type 2 diabetes and heart risk | Weight loss, heart risk and MASH liver disease |
| First FDA approval | 2022 | 2021 |
| Average weight loss in trials | Not listed | 14.9% (STEP 1, 68 weeks) |
| Most common side effect | Nausea 18% vs 4% on placebo | Nausea 44% vs 16% on placebo |
| List price | $1,112.16 per fill | $1,349.02 per month |
| Self-pay from | Not listed | $149 per month |
| Medicare GLP-1 Bridge | Not listed | $50 per month, eligible Part D |
| FDA shortage | Resolved December 19, 2024 | Resolved February 21, 2025 |
Sources: FDA label, FDA label (DailyMed), pricinginfo.lilly.com, TrumpRx.
Weight loss compared
No trial has compared the two drugs directly, so the results come from separate studies of different groups over different lengths.
| Trial | Who took part | Length | Group | Average weight loss | Placebo | A1C change |
|---|---|---|---|---|---|---|
| SURPASS-1 | Adults who had type 2 diabetes and used only diet and exercise | 40 weeks | Tirzepatide 5 mg weekly | Not listed | Not listed | -1.87 percentage points (mean HbA1c change) |
| SURPASS-1 | Adults who had type 2 diabetes and used only diet and exercise | 40 weeks | Tirzepatide 10 mg weekly | Not listed | Not listed | -1.89 percentage points (mean HbA1c change) |
| SURPASS-1 | Adults who had type 2 diabetes and used only diet and exercise | 40 weeks | Tirzepatide 15 mg weekly | Not listed | Not listed | -2.07 percentage points (mean HbA1c change) |
| OASIS 4 | Adults with obesity or overweight, without diabetes | 64 weeks | Wegovy pill 25 mg daily | 13.6% | 2.4% | Not listed |
| STEP 1 | Adults with obesity or overweight, without diabetes | 68 weeks | Semaglutide 2.4 mg weekly | 14.9% | 2.4% | Not listed |
| STEP 2 | Adults with obesity or overweight and type 2 diabetes | 68 weeks | Semaglutide 2.4 mg weekly | 9.6% | 3.4% | Not listed |
Trial sources: SURPASS-1 (PubMed), OASIS 4 (FDA label (DailyMed)), STEP 2 (PubMed), STEP TEENS (PubMed).
Side effects compared
For each label, researchers studied a separate group against that drug's placebo group, so start with each drug's own placebo comparison.
| Side effect | Mounjaro | Placebo (Mounjaro trials) | Wegovy | Placebo (Wegovy trials) |
|---|---|---|---|---|
| Nausea | 18% | 4% | 44% | 16% |
| Diarrhea | 17% | 9% | 30% | 16% |
| Decreased Appetite | 11% | 1% | Not listed | Not listed |
| Vomiting | 9% | 2% | 24% | 6% |
| Dyspepsia | 8% | 3% | 9% | 3% |
| Constipation | 7% | 1% | 24% | 11% |
| Abdominal Pain | 6% | 4% | 20% | 10% |
| Headache | Not listed | Not listed | 14% | 10% |
| Fatigue | Not listed | Not listed | 11% | 5% |
Prices and coverage compared
| Medicine | How you pay | Price |
|---|---|---|
| Mounjaro | List price before insurance | $1,112.16 per fill |
| Mounjaro | Mounjaro Savings Card (insured) | from $25 for up to a 3-month fill |
| Mounjaro | Commercial plan that does not cover it | $499 per month |
| Wegovy | List price before insurance | $1,349.02 per month |
| Wegovy | Wegovy Savings Offer (insured) | from $25 per month |
| Wegovy | Self-pay: Wegovy pill 1.5 mg | $149 per month |
| Wegovy | Self-pay: Wegovy pill 4 mg | $199 per month |
| Wegovy | Self-pay: Wegovy pill 9 mg and 25 mg | $299 per month |
| Wegovy | Self-pay: Wegovy pen intro (first 2 fills at 0.25 mg and 0.5 mg) | $199 per month |
| Wegovy | Self-pay: Wegovy pen 0.25 mg to 2.4 mg | $349 per month |
| Wegovy | Self-pay: Wegovy HD 7.2 mg pen | $399 per month |
| Wegovy | Self-pay via TrumpRx | $149 per month |
| Wegovy | Medicare GLP-1 Bridge (Wegovy, eligible Part D) | $50 per month |
Prices checked November 2026 (7)
pricinginfo.lilly.com, mounjaro.lilly.com, TrumpRx 1 2, NovoCare 1 2, CMS.
Who should pick which?
- Weight loss without diabetes: on its own, Wegovy is approved for this use.
- Type 2 diabetes: only Mounjaro is approved for it
- For MASH liver disease, Wegovy has approval as a treatment.
- Medicare: Wegovy is included in the Medicare GLP-1 Bridge list.
- Cash payments: Wegovy lists $149 per month as its self-pay price.
Your prescriber decides whether to switch, after reviewing your health history, other medicines and coverage.