Zepbound vs Wegovy: Which Weight-Loss Injection Works Better in 2026?

Zepbound produces more weight loss than Wegovy. In the only head-to-head trial, SURMOUNT-5, adults with obesity lost an average of 20.2% of their body weight on Zepbound (tirzepatide) versus 13.7% on Wegovy (semaglutide) over 72 weeks. Wegovy's advantages are a pill version, a 7.2 mg high-dose option that narrows the gap, approved heart protection, and a slightly lower starting self-pay price for the pen.

Here's how the two compare on results, side effects, cost and coverage in October 2026, and how to decide.

SURMOUNT-5 is the cleanest answer. It randomized 751 adults with obesity and no diabetes to the maximum tolerated dose of tirzepatide (10 or 15 mg) or semaglutide (1.7 or 2.4 mg) for 72 weeks. Tirzepatide won on weight (20.2% vs 13.7%) and waist size (about 18 cm vs 13 cm), and more people reached 25% weight loss.

Two caveats. The trial was funded by Lilly, Zepbound's maker. And it compared standard Wegovy 2.4 mg, not Wegovy HD 7.2 mg, which was approved in 2026 and averaged about 21% in its own trial. HD and Zepbound haven't been compared directly, so for people who've plateaued on 2.4 mg, moving up to HD is a reasonable alternative to switching drugs.

Both cause the same family of side effects: nausea, diarrhea, vomiting and constipation, mostly while the dose is increasing. In SURMOUNT-5, rates were broadly similar between the two drugs. Both carry the same class warnings for pancreatitis, gallbladder disease, kidney injury from dehydration, and a boxed warning about thyroid C-cell tumors in rodents. See our side-effects guide.

On self-pay, Zepbound vials through LillyDirect cost $299 for 2.5 mg, $399 for 5 mg and $449 for higher doses. Wegovy pens cost $349 a month ($199 for the first two fills through 2026), Wegovy HD $399 and the pill $149 to $299. With commercial insurance, both have savings cards that can bring copays to about $25. Both are covered through Medicare's GLP-1 Bridge for $50 a month. See our Wegovy cost guide.

For other comparisons, see Mounjaro vs Wegovy and which GLP-1 is best.

Zepbound beats Wegovy 2.4 mg by about six percentage points of body weight in the only head-to-head trial. Wegovy answers with a pill, a 7.2 mg high-dose option and approved heart and liver indications. Prices are close; coverage, health conditions and whether you want a pill usually decide it.