Wegovy vs Mounjaro

Editorial comparison of Wegovy (semaglutide) and Mounjaro (tirzepatide). 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	Wegovy	Mounjaro
Generic name	semaglutide	tirzepatide
Manufacturer	Novo Nordisk	Eli Lilly
FDA approved	2021	2022
Mechanism	Semaglutide mimics GLP-1, a gut hormone released after meals.	Same as Zepbound — dual GLP-1/GIP receptor agonist. Strong glycemic effect plus weight loss.
Dosing	Titrated over 4-5 months: 0.25mg → 0.5mg → 1mg → 1.7mg → 2.4mg, increasing every 4 weeks.	Titrated 2.5mg → 15mg weekly over months, same schedule as Zepbound.
Cost	List price ~$1,350/month without insurance.	Similar to Zepbound — list ~$1,000/month, LillyDirect Self-Pay $399-549/month.
Pivotal trial result	14.9% mean body-weight reduction at 68 weeks	2.0–2.3% HbA1c reduction across SURPASS trials (15 mg dose)

Efficacy in the trials

Wegovy

14.9% mean body-weight reduction at 68 weeks

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

Mounjaro

2.0–2.3% HbA1c reduction across SURPASS trials (15 mg dose)

SURPASS-2 (NCT03987919) — vs semaglutide · Tirzepatide 15 mg achieved 2.30% HbA1c reduction vs 1.86% for semaglutide 1 mg · n=1,879

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

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.

Mounjaro: Titrated 2.5mg → 15mg weekly over months, same schedule as Zepbound.

Cost & access

Mounjaro: Similar to Zepbound — list ~$1,000/month, LillyDirect Self-Pay $399-549/month.

Side effects

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.

Mounjaro: Same as Zepbound.

Which should you choose?

If maximizing average trial weight loss is the priority, Wegovy posted the higher pivotal-trial figure; Mounjaro 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 Wegovy review →

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

Full Mounjaro review →

FDA-approved tirzepatide for type 2 diabetes. Off-label for weight loss is common.

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

Frequently asked

Is Wegovy or Mounjaro more effective?+

In their pivotal trials, Wegovy reported 14.9% mean body-weight reduction at 68 weeks, while Mounjaro reported 2.0–2.3% HbA1c reduction across SURPASS trials (15 mg dose). Head-to-head results vary by patient profile, dose tolerated, and adherence — these trial numbers describe averages, not what every individual experiences.

How do Wegovy and Mounjaro compare on cost?+

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. Mounjaro: Similar to Zepbound — list ~$1,000/month, LillyDirect Self-Pay $399-549/month. Real out-of-pocket depends on insurance formulary tier, manufacturer savings programs, and whether a direct-pay channel is available.

Can I switch from Wegovy to Mounjaro?+

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 Wegovy and Mounjaro the same drug?+

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