Wegovy vs Zepbound
Last reviewed against the current FDA prescribing information for both products. Not medical advice.
Short answer
Wegovy and Zepbound are both once-weekly injections FDA-approved for long-term weight management in adults with obesity, or overweight with a weight-related condition. Wegovy is semaglutide (a GLP-1 receptor agonist); Zepbound is tirzepatide (a GIP and GLP-1 receptor agonist).
In the one published head-to-head trial, SURMOUNT-5 (72 weeks, adults with obesity but without type 2 diabetes, open-label, funded by Eli Lilly), average weight change was −20.2% with tirzepatide (10 or 15 mg) vs −13.7% with semaglutide (1.7 or 2.4 mg) at the highest tolerated doses. The trial did not test the newer 7.2 mg Wegovy dose. Each label also reports its own placebo-controlled results, but those trials used different people and lengths, so compare them with care.
Their other approved uses differ: Wegovy is also approved to lower cardiovascular risk in adults with heart disease and obesity or overweight, for MASH with liver fibrosis, for adolescents 12 and older, and as a daily tablet. Zepbound is also approved for moderate to severe obstructive sleep apnea in adults with obesity. Side effects, coverage and your health history all matter, so choose with your prescriber.
Key differences
- Active ingredient: semaglutide (Wegovy) vs tirzepatide (Zepbound).
- Extra approved uses: cardiovascular risk reduction, MASH and adolescents (Wegovy) vs obstructive sleep apnea (Zepbound).
- Maximum dose: 7.2 mg weekly for adult weight reduction (Wegovy) vs 15 mg weekly (Zepbound).
- Forms: Wegovy has pens, syringes and tablets; Zepbound has single-dose pens, vials and 4-dose KwikPens.
- Head-to-head: SURMOUNT-5 found more weight loss with tirzepatide (−20.2% vs −13.7% at 72 weeks, semaglutide up to 2.4 mg).
Wegovy and Zepbound side by side
| From the FDA label | Wegovy | Zepbound |
|---|---|---|
| Active ingredient | semaglutide | tirzepatide |
| Drug class | GLP-1 receptor agonist | GIP receptor and GLP-1 receptor agonist |
| Manufacturer | Novo Nordisk | Eli Lilly |
| FDA-approved uses |
|
|
| Approved for weight management? | Yes | Yes |
| How it's taken | Injection under the skin (subcutaneous); also approved as a once-daily tablet (25 mg maintenance) | Injection under the skin (subcutaneous) |
| How often | Once weekly (injection) | Once weekly |
| Starting dose | 0.25 mg once weekly for weeks 1–4 | 2.5 mg once weekly for 4 weeks (a starter dose, not a maintenance dose) |
| Dose increases | 0.5 mg (weeks 5–8), 1 mg (weeks 9–12), 1.7 mg (weeks 13–16); escalation can be delayed 4 weeks if a step is not tolerated | Then 5 mg once weekly; can increase in 2.5 mg steps after at least 4 weeks on the current dose |
| Maintenance dose | 2.4 mg (recommended) or 1.7 mg once weekly for most uses | 5 mg, 10 mg or 15 mg once weekly for weight reduction; 10 mg or 15 mg for sleep apnea |
| Maximum dose | 7.2 mg once weekly for weight reduction in adults who have tolerated 2.4 mg for at least 4 weeks and need more weight reduction; 2.4 mg for other uses | 15 mg once weekly |
| When to take it | Same day each week, any time of day, with or without meals | Any time of day, with or without meals. The injection day can be changed if doses are at least 3 days (72 hours) apart |
| Pens and devices | Single-dose pens (0.25 mg to 2.4 mg, plus 7.2 mg "Wegovy HD"), single-dose syringes, and a 4-dose Wegovy FlexTouch pen (2.4 mg) with NovoFine Plus needles included. Tablets: 1.5 mg, 4 mg, 9 mg, 25 mg | Single-dose pens, single-dose vials, 4-dose vials and 4-dose KwikPens, each in 2.5, 5, 7.5, 10, 12.5 and 15 mg strengths |
| Storage | Refrigerate. Single-dose pens and syringes can be kept at 46–86°F for up to 28 days before the cap is removed. FlexTouch: 56 days at room temperature or in the fridge after first use. Do not freeze | Refrigerate. Single-dose pens and vials can be kept unrefrigerated (up to 86°F) for a total of 21 days. KwikPens and multi-dose vials: throw away after 30 days at room temperature, 30 days after first use or 4 weekly doses, whichever comes first. Do not freeze |
| Weight results in the label | In the label’s 68-week trial in adults with obesity, or overweight with a weight-related condition (Study 2), average weight change was −14.9% with Wegovy 2.4 mg vs −2.4% with placebo, on top of diet and exercise. (Wegovy label, section 14.2, Table 8) | In the label’s 72-week trial in adults with obesity, or overweight with a weight-related condition, without type 2 diabetes (Study 1), average weight change was −15.0% (5 mg), −19.5% (10 mg) and −20.9% (15 mg) with Zepbound vs −3.1% with placebo, on top of diet and exercise. (Zepbound label, section 14, Table 2) |
| Most common side effects (≥5%) | Nausea, Diarrhea, Vomiting, Constipation, Abdominal pain, Headache, Fatigue, Indigestion (dyspepsia), Dizziness, Bloating, Belching, Low blood sugar in people with type 2 diabetes, Gas, Stomach flu (gastroenteritis), Acid reflux (GERD), Hair loss, Altered skin sensation (dysesthesia) | Nausea, Diarrhea, Vomiting, Constipation, Abdominal pain, Indigestion (dyspepsia), Injection site reactions, Fatigue, Hypersensitivity (allergic) reactions, Belching, Hair loss, Acid reflux (GERD) |
| Boxed warning | Risk of thyroid C-cell tumors. Do not use if you or a family member have had medullary thyroid carcinoma (MTC) or if you have Multiple Endocrine Neoplasia syndrome type 2 (MEN 2). | Risk of thyroid C-cell tumors. Do not use if you or a family member have had medullary thyroid carcinoma (MTC) or if you have Multiple Endocrine Neoplasia syndrome type 2 (MEN 2). |
| First FDA approval | June 4, 2021 (injection); December 22, 2025 (tablets) | November 8, 2023 |
Side effects listed are the label's “most common adverse reactions”; the full label also covers serious risks such as pancreatitis, gallbladder problems and low blood sugar. Weight results come from separate placebo-controlled trials and are not a head-to-head comparison unless stated.
Good to know
- Wegovy tablets are approved for the adult weight-reduction and cardiovascular uses only, starting at 1.5 mg once daily and stepping up monthly to a 25 mg maintenance dose.
- The label says using Wegovy together with other semaglutide-containing products, or any other GLP-1 receptor agonist, is not recommended.
Questions to ask your prescriber
- Which of these is approved for my diagnosis, and is it covered by my plan?
- How should I step up the dose, and what should I do if the side effects are hard to tolerate?
- Do any of my other medicines, or my personal or family history, rule one of these out?
- If I switch from one to the other, what dose should I start on and when?
Sources
- Wegovy (semaglutide) injection and tablets — FDA prescribing information, DailyMed (label effective June 18, 2026, version 19) (Sections 1, 2, 3, 6, 14.2, 16, boxed warning, Instructions for Use; checked September 24, 2026)
- Drugs@FDA: NDA 215256 (Wegovy injection) (Original approval date (injection); checked September 24, 2026)
- Drugs@FDA: NDA 218316 (Wegovy tablets) (Original approval date (tablets); checked September 24, 2026)
- Zepbound (tirzepatide) injection — FDA prescribing information, DailyMed (label effective August 28, 2026, version 40) (Sections 1, 2, 3, 6, 12.1, 14, 16, boxed warning; checked September 24, 2026)
- Drugs@FDA: NDA 217806 (Zepbound) (Original approval date; checked September 24, 2026)
- Aronne LJ et al. Tirzepatide as Compared with Semaglutide for the Treatment of Obesity (SURMOUNT-5). N Engl J Med 2025;393:26-36 (Head-to-head trial results (abstract); checked September 24, 2026)
How we review: every fact on this page is taken from the current FDA prescribing information on DailyMed or from Drugs@FDA, or from the published trial listed above, and re-checked on the date shown. This page was reviewed against FDA labeling, not by a named clinician.
Medical disclaimer: This page is general information, not medical advice, diagnosis or treatment, and it doesn't cover every use, dose, warning or side effect. Always follow the advice of your doctor, pharmacist or other prescriber and read the Medication Guide that comes with your medicine. If you think you are having a medical emergency, call your local emergency number. ShotWise is a tracking app and does not prescribe, sell or recommend any medication.
