Wegovy vs Zepbound: Which Wins for Weight Loss?

glp-1/does-medicare-cover-glp1">Wegovy vs Zepbound is the head-to-head most weight-loss patients actually care about, and the short answer is that they are two different drugs: Wegovy is semaglutide, a GLP-1 medication, while Zepbound is tirzepatide, a dual GLP-1/GIP medication. In the trials, Zepbound takes off more weight (up to about 20.9% versus about 14.9% for Wegovy), but Wegovy has the larger heart-protection evidence base. Both are once-weekly injections approved specifically for chronic weight management, both work by curbing appetite, and both cost over $1,000 a month at list price. This guide compares Wegovy vs Zepbound on every dimension that matters so you can see the trade-offs at a glance.

Wegovy vs Zepbound at a glance

The table below is the head-to-head summary. The sections after it explain each row.

	Wegovy	Zepbound
Active ingredient	Semaglutide	Tirzepatide
Drug class	GLP-1 agonist	Dual GLP-1 / GIP agonist
Maker	Novo Nordisk	Eli Lilly
Mean weight loss (trial)	~14.9% (STEP-1, 68 wks)	~20.9% (SURMOUNT-1, 72 wks)
How you take it	Once-weekly injection	Once-weekly injection
List price / month	~$1,349	~$1,086
Cheapest cash route	NovoCare ~$499	LillyDirect vials ~$349 to $499
Main side effects	Similar: nausea, diarrhea, constipation, mostly early and dose-related
Bonus approval	Cardiovascular risk reduction	Obstructive sleep apnea

The key difference: two different molecules

This is the part the brand names hide. Wegovy and Zepbound are not the same drug at different prices. Wegovy is semaglutide, which activates one receptor, the GLP-1 receptor. Zepbound is tirzepatide, which activates two, the GLP-1 receptor and the GIP receptor. That second target is the leading explanation for why tirzepatide tends to take off more weight, and it is why the two behave differently even though both reduce appetite. We unpack the mechanism in how tirzepatide works and how semaglutide works for weight loss, and the molecules side by side in semaglutide vs tirzepatide.

Weight loss: Zepbound leads

On the headline number, Wegovy vs Zepbound is not especially close. In STEP-1, the 68-week trial behind Wegovy, the 2.4 mg dose produced about 14.9% mean weight loss. In SURMOUNT-1, the 72-week trial behind Zepbound, the top 15 mg dose produced about 20.9%, with the 10 mg dose around 19.5% and the 5 mg dose around 15.0%. A direct head-to-head trial of the two molecules for weight management also favored tirzepatide. So if maximum weight loss is the single priority, Zepbound has the edge, and a fuller breakdown by drug is in our GLP-1 weight loss results index. The caveat: these are trial averages, individual results vary widely, and Wegovy's roughly 15% is still far beyond what diet alone delivers.

Cost: close, with different cheap routes

Neither is cheap, and what you pay depends far more on your route than on which brand you pick. Wegovy's list price runs higher (around $1,349 a month) than Zepbound's (around $1,086), but both have manufacturer cash options that land in a similar range. Novo Nordisk's NovoCare offers cash Wegovy around $499 a month, and Eli Lilly's LillyDirect sells self-pay Zepbound vials from about $349 to $499. With insurance that covers either drug, both can drop to a $0 to $100 copay, and a savings card can push covered costs lower. The full route-by-route picture for both is in our GLP-1 Cost Index, with brand detail in the Wegovy cost and Zepbound cost guides.

Side effects: similar, GI-led

Wegovy vs Zepbound is close to a tie on tolerability. Both are GLP-1-based, so both share the same main side effects, which are gastrointestinal and concentrated in the first weeks and during dose increases.

Side effect	Wegovy	Zepbound
Nausea	Common, early	Common, early
Diarrhea / constipation	Common	Common
Vomiting, reflux	Less common	Less common
Boxed warning	Thyroid C-cell tumor warning (rodent data); avoid with personal/family history of medullary thyroid cancer or MEN2

Most side effects fade as the body adjusts and are managed by titrating slowly, eating smaller and lower-fat meals, and staying hydrated. See our GLP-1 side effects timeline and managing nausea on GLP-1.

Dosing and how you take them

Both are once-weekly self-injections titrated upward over months to limit nausea, starting low and stepping up every four weeks toward a maintenance dose. Wegovy maintenance is 2.4 mg weekly; Zepbound titrates toward 5, 10, or 15 mg. The practical experience, a small weekly injection you can do at home, is essentially the same for both. Our pre-GLP-1 checklist covers what to know before the first dose.

How fast you will see results

Neither drug works overnight, and the pace is similar for both. Because each is titrated upward slowly to limit nausea, the first month or two is mostly about reaching a dose that does the work, not maximum weight loss. Most people see the scale start to move within the first one to two months, with the steepest loss through the middle of the course as the dose climbs, then a gradual flattening as the body approaches a new set point. In the trials, weight was still falling at six months and only leveled off later, which is why both Wegovy and Zepbound are treatments you stay on rather than short courses. Stopping either tends to reverse much of the loss, so the comparison that matters is not just which takes off more weight, but which you can access and tolerate for the long run. We cover what that looks like in realistic weight loss goals on GLP-1 and weight regain after stopping.

Beyond weight: heart vs sleep apnea

This is where Wegovy vs Zepbound genuinely diverge, and it can decide the choice. Wegovy carries an FDA approval to reduce the risk of cardiovascular events (heart attack and stroke) in adults with established heart disease and obesity, backed by a large outcomes trial. Zepbound carries an FDA approval for moderate-to-severe obstructive sleep apnea in adults with obesity, the first drug approved for that condition, which we cover in Zepbound for sleep apnea. If you have heart disease, Wegovy's evidence may matter; if you have sleep apnea, Zepbound's approval can also help with insurance coverage.

Which should you choose?

There is no universal winner in Wegovy vs Zepbound, but the decision usually comes down to a few factors:

• Maximum weight loss: Zepbound has the edge in trials (~20.9% vs ~14.9%).
• Heart disease: Wegovy has the cardiovascular approval and outcomes data.
• Sleep apnea: Zepbound is FDA-approved for it, which can aid coverage.
• Cost and access: compare your specific insurance and the cash routes for each; the cheapest option varies by person.
• Tolerability: similar, but individuals respond differently, and sometimes the one your plan covers is the practical answer.

Either way, this is a prescription decision made with a licensed clinician, who can weigh your weight-loss goal against your heart, sleep, and metabolic health. For the diabetes-brand versions of these same molecules, see Ozempic vs Wegovy and Mounjaro vs Zepbound.