GLP-1 medicines
Zepbound vs Wegovy: what the two labels actually differ on
Most comparisons argue about which works better. This one sets the two prescribing informations next to each other and reports where they differ, which turns out to be in places people rarely look.
Side by side
| Zepbound | Wegovy | |
|---|---|---|
| Drug | tirzepatide | semaglutide |
| Acts on | GIP and GLP-1 receptors | GLP-1 receptors |
| How often | Once weekly | Once weekly |
| Starting dose | 2.5 mg for 4 weeks | 0.25 mg for 4 weeks |
| Steps | 2.5 mg increments, ≥4 weeks each | 0.5 → 1 → 1.7 mg, 4 weeks each |
| Maintenance | 5, 10 or 15 mg | 1.7 or 2.4 mg |
| Maximum | 15 mg weekly | 2.4 mg weekly |
| Injection sites | Abdomen, thigh; back of the upper arm only if someone else injects | Abdomen, thigh or upper arm |
| Missed dose | Take within 4 days (96 hours), else skip | Take if the next dose is more than 2 days (48 hours) away, else skip |
| Also approved for | Obstructive sleep apnea in adults with obesity | — |
The milligram numbers are not comparable. 15 mg of Zepbound is not "six times stronger" than 2.4 mg of Wegovy — they are different molecules at different potencies. Comparing the numbers is the single most common mistake people make with this pair.
What is the same
Both carry the FDA's strongest warning, and it is nearly word for word the same: in rodents, the drug caused dose-dependent and treatment-duration-dependent thyroid C-cell tumors at clinically relevant exposures.
Both are contraindicated — not cautioned, contraindicated — for anyone with:
- a personal or family history of medullary thyroid carcinoma;
- multiple endocrine neoplasia syndrome type 2;
- a prior serious hypersensitivity reaction to the drug or its ingredients.
Both share the same shape of side effect: digestive, concentrated after each dose increase, and the reason a minority of people stop.
Where the real differences sit
The missed-dose window. Zepbound gives you four days; Wegovy asks whether the next scheduled dose is more than two days away. Someone switching between them and carrying over the old rule will get it wrong.
The upper arm. Wegovy's label lists it as a site you may use. Zepbound's makes it conditional on another person doing the injection.
Sleep apnea. Zepbound carries an approval for obstructive sleep apnea in adults with obesity, at 10 mg or 15 mg. Wegovy does not. If sleep apnea is part of the picture, that is a real difference rather than a marketing one.
What this page will not do
Tell you which is better. That depends on your history, what your insurance covers, what is in stock and how you tolerate the first weeks — and it is a decision for a licensed clinician, not a table.
Where this came from
- FDA, Highlights of Prescribing Information: ZEPBOUND (tirzepatide) injection, 2025 revision — accessdata.fda.gov
- openFDA drug label API, ZEPBOUND and WEGOVY records, retrieved 23 September 2026 — api.fda.gov