If you're considering a GLP-1 medication for weight loss, the two names you'll hear most often are Wegovy (semaglutide) and Zepbound (tirzepatide). Both are FDA-approved specifically for chronic weight management, both are once-weekly injections, and both have strong clinical data behind them. But they work differently under the hood, and the practical differences in effectiveness, side effects, dosing, and cost can matter quite a bit.
This guide breaks down how the two compare so you can have a more informed conversation with your doctor about which might be the better fit.
Wegovy contains semaglutide, which mimics a single gut hormone called GLP-1. This hormone signals your brain to feel full, slows stomach emptying, and helps regulate blood sugar.
Zepbound contains tirzepatide, which mimics two gut hormones: GLP-1 and GIP (glucose-dependent insulinotropic polypeptide). The dual-hormone approach appears to provide stronger appetite suppression and may influence how your body processes and stores fat differently than GLP-1 alone.
Think of it this way: Wegovy pulls one lever. Zepbound pulls two. Whether pulling two levers produces meaningfully better results for you specifically depends on your individual biology, which is something clinical trials can only approximate at a population level.
In head-to-head clinical trials, tirzepatide (Zepbound) produced greater average weight loss than semaglutide (Wegovy). Here's what the data shows:
| Metric | Wegovy (2.4 mg) | Zepbound (15 mg) |
|---|---|---|
| Avg. body weight loss | ~15% over 68 weeks | ~21% over 72 weeks |
| Patients losing ≥10% | ~69% | ~84% |
| Patients losing ≥20% | ~32% | ~56% |
These numbers are population averages from clinical trials, which means your individual results could be higher or lower. Some people respond very well to semaglutide and less so to tirzepatide, or vice versa. The trial data gives Zepbound an edge on paper, but "better on average" doesn't always mean "better for you."
Both medications start at a low dose and gradually increase to reduce side effects. The titration schedules look different though:
| Phase | Wegovy | Zepbound |
|---|---|---|
| Starting dose | 0.25 mg weekly | 2.5 mg weekly |
| Titration steps | 5 doses (0.25 → 0.5 → 1 → 1.7 → 2.4 mg) | 6 doses (2.5 → 5 → 7.5 → 10 → 12.5 → 15 mg) |
| Time between increases | 4 weeks each | 4 weeks each |
| Time to maintenance dose | ~16 weeks (4 months) | ~20 weeks (5 months) |
| Maintenance dose | 2.4 mg | 5 mg, 10 mg, or 15 mg |
One notable difference: Zepbound offers more flexibility in maintenance dosing. Your doctor can keep you at 5 mg, 10 mg, or increase to the maximum 15 mg based on how you're responding. Wegovy's target maintenance dose is 2.4 mg for everyone, though some patients stay at 1.7 mg if they can't tolerate the higher dose.
Both medications share the same core side effects because they work on similar pathways. The most common include nausea, vomiting, diarrhea, constipation, and stomach pain. These tend to be worst during the first few weeks at each new dose and typically improve as your body adjusts.
Clinical trial data shows broadly similar side effect rates between the two, though some patients report that one is more tolerable than the other. There's no reliable way to predict which you'll tolerate better before trying it. If you have a rough time with one, switching to the other is a reasonable conversation to have with your doctor.
| Scenario | Wegovy | Zepbound |
|---|---|---|
| List price | ~$1,349/mo | ~$1,086/mo |
| Manufacturer direct-pay (no insurance) | $149-$299/mo via NovoCare | $299-$449/mo via LillyDirect |
| With commercial insurance + savings card | As low as $25/mo | As low as $25/mo |
| Medicare (starting July 2026) | $50/mo via GLP-1 Bridge | $50/mo via GLP-1 Bridge |
Cost can vary dramatically depending on your insurance, and it changes frequently. For current estimates tailored to your situation, try our Cost Estimator tool.
Both medications now have oral (pill) versions in development or available. The Wegovy pill (oral semaglutide 25 mg) was approved by the FDA in December 2025 and is available now. A tirzepatide pill is expected to receive FDA approval sometime in 2026 after being granted fast-track status.
The Wegovy pill has shown similar weight loss effectiveness to the injection in clinical trials, which is a meaningful option for people who prefer not to inject.
There's no universal answer here. A few considerations that might help frame your conversation with your doctor:
Zepbound may be worth discussing if maximizing weight loss is your primary goal, if you want more flexibility in maintenance dosing, or if you've tried semaglutide and the results were underwhelming.
Wegovy may be worth discussing if you prefer having an oral (pill) option available now, if you have cardiovascular risk factors (Wegovy has more long-term cardiovascular outcome data), or if your insurance covers it but not Zepbound.
For many people, the deciding factor ends up being practical: which one does your insurance cover, and which can you afford? That's not a bad way to decide, because both medications are effective and well-studied.
Use our free calculator to see your titration schedule, track your progress, and estimate costs.
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