Is tirzepatide better than semaglutide?
How do semaglutide and tirzepatide compare for weight loss and side effects?
For weight loss, the head-to-head data favor tirzepatide. In SURMOUNT-5, adults with obesity lost 20.2% of their body weight at 72 weeks on tirzepatide and 13.7% on semaglutide. In type 2 diabetes, SURPASS-2 found tirzepatide lowered HbA1c and weight more than semaglutide 1 mg. Side effects were similar in kind, mostly stomach and gut.[1][2]
Semaglutide vs Tirzepatide at a glance
Prices checked October 3, 2026.
| Attribute | Semaglutide semaglutide | HIGHLIGHTED Tirzepatidetirzepatide |
|---|---|---|
| Active ingredient | semaglutide | tirzepatide |
| Manufacturer | Novo Nordisk | Eli Lilly |
| Drug class | GLP-1 receptor agonist | Dual GIP / GLP-1 receptor agonist |
| FDA approved | December 2017 (Ozempic) · June 2021 (Wegovy) | May 2022 (Mounjaro) · November 2023 (Zepbound) |
| Indication | Type 2 diabetes, plus heart and kidney risk (Ozempic). Weight management, heart risk, and MASH (Wegovy)[3][4] | Type 2 diabetes, plus heart risk (Mounjaro). Weight management and sleep apnea (Zepbound)[5][6] |
| Dose schedule | Subcutaneous injection (weekly) · oral tablet (daily) · Once weekly (injectable)[3][4][15] | Subcutaneous injection · Once weekly[5][6] |
| Available doses | 0.25 mg · 0.5 mg · 1 mg · 1.7 mg · 2.4 mg · 7.2 mg (Wegovy HD)[3][4] | 2.5 mg · 5 mg · 7.5 mg · 10 mg · 12.5 mg · 15 mg[5][6] |
| Mechanism | Semaglutide is a GLP-1 analog with 94% homology to native human GLP-1. It binds the GLP-1 receptor, augmenting glucose-dependent insulin secretion, suppressing glucagon, slowing gastric emptying, and reducing appetite via central nervous system pathways. | Tirzepatide is a first-in-class single molecule that activates both the GIP and GLP-1 receptors. The dual incretin action augments glucose-dependent insulin secretion, suppresses glucagon, slows gastric emptying, and reduces appetite. It produces larger average weight and HbA1c reductions than GLP-1 agonism alone in head-to-head trials. |
| Common side effects | Nausea 15.8 to 20.3% (Ozempic 0.5 mg and 1 mg) and 44% (Wegovy 2.4 mg). Diarrhea 8.5 to 8.8% (Ozempic 0.5 mg and 1 mg) and 30% (Wegovy 2.4 mg). Vomiting 5 to 9.2% (Ozempic 0.5 mg and 1 mg) and 24% (Wegovy 2.4 mg)[3][4] | Nausea 12 to 18% (Mounjaro) and 25 to 29% (Zepbound) at 5 mg to 15 mg. Diarrhea 12 to 17% (Mounjaro) and 19 to 23% (Zepbound). Vomiting 5 to 9% (Mounjaro) and 8 to 13% (Zepbound)[5][6] |
| Cost range | List price $1,027.51 (Ozempic) and $1,349.02 (Wegovy) a month. Self-pay pen $349 to $499 through Novo Nordisk. As little as $25 with commercial insurance[7][8][13][11] | List price $1,112.16 (Mounjaro) and $1,086.37 (Zepbound) a month. Self-pay $299 to $699 through Lilly. As little as $25 with commercial insurance[9][10][14][12][16] |
This comparison is for education only and is not medical advice. Semaglutide and tirzepatide are prescription medicines with distinct FDA-approved indications. Whether either is appropriate for you, and at what dose, is a decision for a licensed clinician.
Is tirzepatide better than semaglutide for weight loss?
In SURMOUNT-5 it was. The trial gave 751 adults with obesity and no diabetes the highest dose they tolerated for 72 weeks: tirzepatide 10 or 15 mg, or semaglutide 1.7 or 2.4 mg. Weight fell 20.2% on tirzepatide and 13.7% on semaglutide. Waist size fell 18.4 cm and 13.0 cm. The trial was open-label and funded by Eli Lilly. The semaglutide weight loss calculator and the tirzepatide weight loss calculator chart average loss week by week from trial data.[1]
Is tirzepatide better than semaglutide for type 2 diabetes?
In SURPASS-2, 1,879 adults with type 2 diabetes took tirzepatide 5, 10, or 15 mg or semaglutide 1 mg for 40 weeks. HbA1c fell 2.01 to 2.30 points on tirzepatide and 1.86 points on semaglutide. Weight loss was 1.9 to 5.5 kg greater on tirzepatide.[2]
Which has more side effects, semaglutide or tirzepatide?
Both mostly cause stomach and gut side effects. In SURPASS-2, nausea hit 17 to 22% on tirzepatide and 18% on semaglutide. Serious adverse events were 5 to 7% on tirzepatide and 3% on semaglutide. In SURMOUNT-5, most side effects in both groups were mild to moderate and showed up while the dose was going up.[2][1]
| Side effect | Ozempic 0.5 mg and 1 mg | Wegovy 2.4 mg | Mounjaro 5 mg to 15 mg | Zepbound 5 mg to 15 mg |
|---|---|---|---|---|
| Nausea | 15.8% to 20.3% | 44% | 12% to 18% | 25% to 29% |
| Diarrhea | 8.5% to 8.8% | 30% | 12% to 17% | 19% to 23% |
| Vomiting | 5% to 9.2% | 24% | 5% to 9% | 8% to 13% |
| Constipation | 3.1% to 5% | 24% | 6% to 7% | 11% to 17% |
Why would a doctor prescribe semaglutide instead of tirzepatide?
The labels give some reasons. Semaglutide has approvals tirzepatide lacks. Wegovy is approved to lower heart attack and stroke risk in adults with heart disease and obesity or overweight, while Mounjaro's heart approval covers only adults with type 2 diabetes. Wegovy also treats the liver disease MASH and is approved for weight management in children 12 and older. Ozempic lowers the risk of kidney failure in adults with type 2 diabetes and chronic kidney disease. Semaglutide also comes as a daily tablet, and Mounjaro and Zepbound come only as injections. Tirzepatide has two approvals semaglutide lacks: obstructive sleep apnea in adults with obesity, as Zepbound, and type 2 diabetes in children 10 and older, as Mounjaro.[4][3][15][5][6]
What not to mix with semaglutide?
The Wegovy label says not to use it with other semaglutide products or any other GLP-1 receptor agonist, and the Zepbound label says the same for tirzepatide. So the two drugs are not taken together. Both semaglutide labels warn that using it with insulin or a sulfonylurea raises the risk of low blood sugar, and that slower stomach emptying can change how other pills are absorbed. The tirzepatide labels add one more: people on birth control pills should switch to a non-oral method or add a barrier method for 4 weeks after starting and after each dose increase.[4][3][5][6]
Is semaglutide or tirzepatide cheaper?
Neither drug is sold by its own name. Price depends on the brand. At list price, the four brands run from $1,027.51 a month for Ozempic to $1,349.02 for Wegovy. Paying cash through the makers, Zepbound KwikPens run from $299 at the 2.5 mg starting dose to $699 at 10 mg and above. From 7.5 mg up, a first purchase or a refill within 45 days costs $449. Novo Nordisk pens are $349 at most doses, and its semaglutide tablets start at $149. With commercial insurance that covers the brand, each maker's savings card can bring a fill to as little as $25.[7][8][9][10][11][12][13][14][16]
Prices checked October 3, 2026.
| Monthly price | Ozempic | Wegovy | Mounjaro | Zepbound |
|---|---|---|---|---|
| List price | $1,027.51 | $1,349.02 | $1,112.16 | $1,086.37 |
| Self-pay through the maker | $349 to $499 | $349 to $399 | From $499 | $299 to $699 |
| Commercial insurance with the savings card | As little as $25 | As little as $25 | As little as $25 | As little as $25 |
Which brands contain semaglutide and tirzepatide?
Semaglutide is sold as Ozempic for type 2 diabetes and Wegovy for weight management. Tirzepatide is sold as Mounjaro for type 2 diabetes and Zepbound for weight management and sleep apnea in adults with obesity. Compare the brands in Mounjaro vs Ozempic, Wegovy vs Zepbound, and Wegovy vs Mounjaro.[3][4][5][6]
- Aronne LJ et al. Tirzepatide as Compared with Semaglutide for the Treatment of Obesity. N Engl J Med 2025;393:26-36 (SURMOUNT-5) (NEJM)
- Frías JP et al. Tirzepatide versus Semaglutide Once Weekly in Patients with Type 2 Diabetes. N Engl J Med 2021;385:503-515 (SURPASS-2) (NEJM)
- FDA label, Ozempic (semaglutide) injection, Novo Nordisk (DailyMed)
- FDA label, Wegovy (semaglutide) injection and tablets, Novo Nordisk (DailyMed)
- FDA label, Mounjaro (tirzepatide) injection, Eli Lilly (DailyMed)
- FDA label, Zepbound (tirzepatide) injection, Eli Lilly (DailyMed)
- Ozempic list price (wholesale acquisition cost), Novo Nordisk Pricing, May 2026 (Novo Nordisk)
- Wegovy list price (wholesale acquisition cost), Novo Nordisk Pricing, March 2026 (Novo Nordisk)
- Mounjaro list price (wholesale acquisition cost), Lilly pricing information, read October 3, 2026 (Eli Lilly)
- Zepbound list price and self-pay prices, Lilly pricing information, read October 3, 2026 (Eli Lilly)
- Wegovy cost and coverage: savings card, self-pay prices, and the Medicare GLP-1 Bridge, read October 3, 2026 (Novo Nordisk)
- Zepbound savings card, self-pay offers, and the Medicare GLP-1 Bridge, read October 3, 2026 (Eli Lilly)
- Ozempic cost and coverage: savings card and self-pay prices, read October 3, 2026 (Novo Nordisk)
- Mounjaro self-pay price on LillyDirect, read October 3, 2026 (Eli Lilly)
- FDA label, Rybelsus and Ozempic (semaglutide) tablets, Novo Nordisk (DailyMed)
- Mounjaro savings card terms, read October 3, 2026 (Eli Lilly)