Guide · 8 min read
Zepbound vs. Wegovy
Two weekly injections, two different molecules, and a lot of confusing headlines. Here's an honest, plain-language comparison of how they work, what to expect week by week, and what actually matters when you're choosing.
The short version
Wegovy is semaglutide — it mimics one gut hormone, GLP-1. Zepbound is tirzepatide — it mimics two, GLP-1 and GIP. On average, Zepbound produces more weight loss in trials. Wegovy has the longer track record and, for many people, easier insurance coverage. Both only work while you keep taking them, and both depend far more on tolerating the ramp-up than on which one you picked.
Side-by-side
| Attribute | Wegovy | Zepbound |
|---|---|---|
| Active ingredient | Semaglutide | Tirzepatide |
| Drug class | GLP-1 receptor agonist | GIP + GLP-1 dual agonist |
| Approved for | Chronic weight management | Chronic weight management + obstructive sleep apnea |
| How you take it | Weekly injection | Weekly injection |
| Starting dose | 0.25 mg/week | 2.5 mg/week |
| Top maintenance dose | 2.4 mg/week | 15 mg/week |
| Titration length | ~16 weeks to full dose | ~20 weeks to top dose |
| Avg. weight loss in trials | ~15% at 68 weeks (STEP 1) | ~21% at 72 weeks (SURMOUNT-1) |
| Common side effects | Nausea, constipation, reflux, fatigue | Same profile — some tolerate it better |
| US list price, no insurance | ~$1,350/mo | ~$1,060/mo |
Efficacy: what the trials showed
STEP 1 tested Wegovy at 2.4 mg and found about 15% average body-weight loss at 68 weeks. SURMOUNT-1 tested Zepbound at 10–15 mg and found about 21% at 72 weeks. SURMOUNT-5, a head-to-head trial, also favored tirzepatide.
Averages hide a wide spread. Plenty of people lose more than 20% on Wegovy, and plenty plateau in the low teens on Zepbound. Adherence, protein intake, sleep, movement, and how long you stay on the medication move the number more than the brand does.
Titration schedules
Both ramp slowly on purpose — going up faster mostly buys you more nausea. Your prescriber may hold you at a dose longer if side effects are rough, and that's normal.
| Timing | Wegovy | Zepbound |
|---|---|---|
| Weeks 1–4 | 0.25 mg | 2.5 mg |
| Weeks 5–8 | 0.5 mg | 5 mg |
| Weeks 9–12 | 1 mg | 7.5 mg |
| Weeks 13–16 | 1.7 mg | 10 mg |
| Weeks 17–20 | 2.4 mg (maintenance) | 12.5 mg |
| Week 21+ | 2.4 mg | 15 mg (maintenance) |
Side effects
Nausea, constipation, reflux, fatigue, and burping show up on both. They cluster in the two to three days after an injection and after every dose increase, then usually settle. Rarer but serious risks — pancreatitis, gallbladder problems, and a boxed warning about thyroid C-cell tumors based on rodent studies — apply to both.
There's no way to predict which one you'll tolerate better. Tracking your symptoms against your dose day is the fastest way to learn your own pattern, which is exactly what the nausea guide walks through.
Cost and coverage
US list prices are in the same neighborhood — roughly $1,060/month for Zepbound and $1,350/month for Wegovy before savings programs. What actually decides your cost is your insurer's formulary. Both manufacturers run direct-pay programs for people paying cash, and prices shift often enough that it's worth re-checking every few months.
Switching between them
Switching is common — usually for tolerability, a plateau, coverage, or supply. You don't carry your dose over: most people restart Zepbound at 2.5 mg even after months on Wegovy's top dose. Expect the early side effects to return briefly while you re-titrate.
So which one?
That's a decision for you and your prescriber, shaped by your coverage, your other conditions, and how your body responds. What we'd gently push back on is treating the choice as the whole game. The people who do best are the ones who ride out the ramp-up, eat enough protein, and stay on long enough to see the curve bend — on either medication.
Track either one in Dosejoy
Log doses, symptoms, protein, and weight in one place — and see exactly how each dose increase treats you.
Start free →Not medical advice. Trial figures are approximate and depend on dose, duration, and adherence. Always follow your prescriber.