Zepbound vs Wegovy

Editorial comparison of Zepbound (tirzepatide) and Wegovy (semaglutide). Same drug class context, trial-anchored data, no marketing claims.

Reviewed by the WeighedHealth Editorial Team against primary clinical sources — FDA labeling, peer-reviewed trials, and specialty-society guidelines.

Content current as of July 2026; updated when guidance or availability changes.

Side-by-side

Dimension	Zepbound	Wegovy
Generic name	tirzepatide	semaglutide
Manufacturer	Eli Lilly	Novo Nordisk
FDA approved	2023	2021
Mechanism	Tirzepatide is a dual incretin agonist: it hits both the GLP-1 receptor (like semaglutide) and the GIP receptor (which semaglutide doesn't).	Semaglutide mimics GLP-1, a gut hormone released after meals.
Dosing	Titrated 2.5mg → 5mg → 7.5mg → 10mg → 12.5mg → 15mg, every 4 weeks. Maintenance 5-15mg weekly depending on tolerability and target weight.	Titrated over 4-5 months: 0.25mg → 0.5mg → 1mg → 1.7mg → 2.4mg, increasing every 4 weeks.
Cost	List price ~$1,000-1,300/month.	List price ~$1,350/month without insurance.
Pivotal trial result	20.9% mean body-weight reduction at 72 weeks (15 mg dose)	14.9% mean body-weight reduction at 68 weeks

Efficacy in the trials

Zepbound

20.9% mean body-weight reduction at 72 weeks (15 mg dose)

SURMOUNT-1 (NCT04184622) · vs 3.1% with placebo · n=2,539

Wegovy

14.9% mean body-weight reduction at 68 weeks

STEP 1 (NCT03548935) · vs 2.4% with placebo + lifestyle · n=1,961

Trial averages describe study populations, not individuals. Response varies with the dose tolerated, adherence, and personal physiology; the two drugs were not necessarily tested head-to-head in the same trial.

The details

Dosing & cadence

Zepbound: Titrated 2.5mg → 5mg → 7.5mg → 10mg → 12.5mg → 15mg, every 4 weeks. Maintenance 5-15mg weekly depending on tolerability and target weight.

Wegovy: Titrated over 4-5 months: 0.25mg → 0.5mg → 1mg → 1.7mg → 2.4mg, increasing every 4 weeks. Maintenance dose 2.4mg weekly. Slower titration is common to manage GI side effects.

Cost & access

Wegovy: List price ~$1,350/month without insurance. With Novo Nordisk's patient assistance program, eligible self-pay patients can access at $200-500/month. Insurance coverage is patchy and often requires prior authorization plus a documented weight-related comorbidity.

Side effects

Zepbound: Similar profile to semaglutide: nausea, constipation, diarrhea, fatigue. Some patients report stronger GI side effects than Wegovy at equivalent body-weight-loss-effectiveness doses; others tolerate it better. Same MTC/MEN2 contraindication.

Wegovy: Most common: nausea (especially first 4-8 weeks), constipation, diarrhea, fatigue, headache. Less common: gallbladder issues, pancreatitis (rare), kidney strain if dehydrated. Black-box warning: medullary thyroid cancer risk (theoretical, based on rodent studies). Discontinue and consult clinician for severe abdominal pain or persistent vomiting.

Which should you choose?

If maximizing average trial weight loss is the priority, Zepbound posted the higher pivotal-trial figure; Wegovy still produced clinically meaningful loss and some people tolerate it better. On cost and access, compare each drug's manufacturer direct-pay and insurance path — that often matters more month-to-month than the efficacy gap. Both carry class safety considerations (see each drug's boxed-warning and contraindications); a personal or family history of medullary thyroid carcinoma or MEN2 rules out the GLP-1 class. Bring this comparison to a prescriber, who will match the drug to your history and titrate the dose.

This is editorial framing, not a prescription. The right choice depends on your medical history, insurance, and a clinician's evaluation.

Full Zepbound review →

Dual GLP-1/GIP agonist for weight management. ~20% body weight loss in trials — strongest weight-loss drug currently available.

Full Wegovy review →

Once-weekly injectable semaglutide for chronic weight management. ~15% body weight loss in trials.

Deciding at the molecule level? Semaglutide vs Tirzepatide compares the two drug families behind every major GLP-1 brand.

Frequently asked

Is Zepbound or Wegovy more effective?+

In their pivotal trials, Zepbound reported 20.9% mean body-weight reduction at 72 weeks (15 mg dose), while Wegovy reported 14.9% mean body-weight reduction at 68 weeks. Head-to-head results vary by patient profile, dose tolerated, and adherence — these trial numbers describe averages, not what every individual experiences.

How do Zepbound and Wegovy compare on cost?+

Zepbound: List price ~$1,000-1,300/month. Lilly's patient assistance program (LillyDirect Self-Pay) offers $399-549/month for self-pay patients depending on dose. Insurance coverage similar pattern to Wegovy. Wegovy: List price ~$1,350/month without insurance. With Novo Nordisk's patient assistance program, eligible self-pay patients can access at $200-500/month. Insurance coverage is patchy and often requires prior authorization plus a documented weight-related comorbidity. Real out-of-pocket depends on insurance formulary tier, manufacturer savings programs, and whether a direct-pay channel is available.

Can I switch from Zepbound to Wegovy?+

Switching between brand-name treatments in the same drug class is common, but the conversion is not always 1:1. Discuss the switch with your prescriber — they'll usually re-titrate dosing rather than substitute equivalent strengths directly.

Are Zepbound and Wegovy the same drug?+

No. Zepbound (tirzepatide) and Wegovy (semaglutide) are distinct medications from Eli Lilly and Novo Nordisk respectively. They may share a drug class or mechanism but differ in active ingredient, dosing, and approved use.