This page is for informational purposes only. It is not medical advice. Talk to your doctor before starting, changing, or stopping any medication.
Zepbound vs Wegovy (2026)
Quick answer
In the SURMOUNT-5 head-to-head trial, Zepbound (tirzepatide) showed greater average weight loss than Wegovy (semaglutide). Both drugs are effective for weight loss. Zepbound won on all primary endpoints in that trial.
Zepbound vs Wegovy: Side-by-Side
| Feature | Zepbound | Wegovy |
|---|---|---|
| Active ingredient | Tirzepatide | Semaglutide |
| Drug class | Dual GIP/GLP-1 | GLP-1 only |
| FDA approval year | 2023 | 2021 |
| Max dose | 15 mg/week | 2.4 mg/week |
| Avg weight loss (clinical trial) | 20.9% (SURMOUNT-1) | 15-17% (STEP) |
| Trial name | SURMOUNT | STEP |
| Cost without insurance | ~$1,060/mo | ~$1,349/mo |
| Insurance coverage | Yes, with prior auth | Yes, with prior auth |
SURMOUNT-5: The Head-to-Head Trial
SURMOUNT-5 is the only published head-to-head trial comparing Zepbound and Wegovy directly in adults with obesity. Here are the key results:
- Zepbound average weight loss: 20.2%
- Wegovy average weight loss: 13.7%
- 47% of Zepbound patients lost 25% or more of body weight
- 27% of Wegovy patients lost 25% or more of body weight
- Zepbound won on all primary endpoints
These results do not mean Wegovy is a bad drug. 13.7% average weight loss is still a large clinical result. For context, most non-GLP-1 weight loss medications produce less than 5% average body weight loss.
Why Zepbound Shows Greater Weight Loss
Wegovy works by activating GLP-1 receptors. These receptors slow gastric emptying, reduce appetite, and improve insulin signaling.
Zepbound adds GIP receptor activation on top of GLP-1 activity. GIP is a second gut hormone that also influences appetite and fat metabolism. The dual action of Zepbound is the leading explanation for why it produces greater weight loss in clinical trials.
Side Effect Comparison
Both drugs share a similar side effect profile because they work on overlapping receptors.
- Nausea (most common, especially at dose increases)
- Vomiting
- Diarrhea
- Constipation
- Injection site reactions
Zepbound has a slightly higher nausea rate at maximum dose compared to Wegovy in trial data. Side effects typically improve after the first 4 to 8 weeks on a stable dose. Slow titration reduces severity.
Cost and Insurance
Wegovy has historically had broader insurance coverage because it launched two years before Zepbound and has been on insurer formularies longer. Coverage for Zepbound is growing as it gains market share.
Both Novo Nordisk (Wegovy) and Eli Lilly (Zepbound) offer manufacturer savings programs that can reduce out-of-pocket costs for commercially insured patients.
Compounded versions of both semaglutide and tirzepatide are available through licensed telehealth pharmacies when the branded drugs are on the FDA shortage list. Always verify current FDA shortage status before ordering compounded versions.
Who Should Choose Zepbound
- Those without insurance coverage who want the drug with the best head-to-head data
- Those whose insurance covers Zepbound on their formulary
- Those who have not responded well to GLP-1-only therapy
- Those who want the higher average weight loss ceiling
Who Should Choose Wegovy
- Those whose insurance specifically covers Wegovy and not Zepbound
- Those who prefer the longer market track record since 2021
- Those who have already had success on semaglutide-based therapy
Frequently Asked Questions
Is Zepbound better than Wegovy?
In the SURMOUNT-5 head-to-head trial, Zepbound produced greater average weight loss than Wegovy — 20.2% versus 13.7%. Zepbound won on all primary endpoints in that trial. However, both drugs are effective, and the best choice depends on your insurance coverage, prescriber recommendation, and individual response. Talk to your doctor.
Can you switch from Wegovy to Zepbound?
Yes. Switching between GLP-1 medications is possible under physician supervision. Your doctor will guide the transition, which usually involves stopping one drug and starting the other at a low dose before titrating up. Never switch without medical guidance.
Does insurance cover both Zepbound and Wegovy?
Both require prior authorization from most insurers. Coverage varies widely by plan. Wegovy has historically had broader insurance coverage since it launched in 2021. Zepbound launched in 2023 and coverage is expanding. Check your specific plan formulary. Medicare Part D does not cover either for weight loss as of 2025.
What is the cheapest way to get Zepbound or Wegovy?
If you have commercial insurance, prior authorization plus the manufacturer savings card is the cheapest route. Without insurance, compounded semaglutide or tirzepatide through licensed telehealth platforms is usually the most affordable option, often $99 to $400 per month depending on dose and provider. Check current FDA shortage status before ordering compounded versions.
The right GLP-1 medication for you depends on your health history, insurance plan, and what your doctor recommends. Talk to your doctor before starting, changing, or stopping any weight loss medication.