Ozempic vs Wegovy vs Mounjaro vs Zepbound — What's the Difference?
A practical educational comparison of the four major GLP-1 medications — their active ingredients, approved uses, weight loss trial data, and key differences to discuss with your prescriber.
Last reviewed: May 2026
Medication decisions are personal. This page compares approved medications based on publicly available trial data and FDA labeling. Use it to prepare better questions for the prescriber who knows your health history.
The four major GLP-1 medications
Two drugs (semaglutide and tirzepatide), four brand names, two approved use cases each.
Ozempic
by Novo Nordisk
Class
GLP-1 receptor agonist
Approved for
Type 2 diabetes management
Avg weight loss
~15%
Trial data
SUSTAIN trials
FDA-approved for diabetes. Widely prescribed off-label for weight loss.
Note: Not FDA-approved for weight loss — Wegovy (same drug, different dose) is. Some insurance covers Ozempic for diabetes but not weight.
Wegovy
by Novo Nordisk
Class
GLP-1 receptor agonist
Approved for
Chronic weight management (BMI ≥30 or ≥27 with comorbidity)
Avg weight loss
~15–17%
Trial data
STEP trials
Same active ingredient as Ozempic but at a higher dose, specifically approved for weight loss.
Note: Also FDA-approved to reduce cardiovascular risk in people with obesity + CVD. FDA shortage restrictions have eased as supply stabilized into 2026.
Mounjaro
by Eli Lilly
Class
GLP-1 + GIP dual receptor agonist
Approved for
Type 2 diabetes management
Avg weight loss
~20–22%
Trial data
SURPASS trials
FDA-approved for diabetes. Dual mechanism (GLP-1 + GIP) appears to produce greater weight loss than semaglutide.
Note: Not FDA-approved for weight loss — Zepbound (same drug) is. SURMOUNT trials showed ~20%+ weight loss at the highest dose.
Zepbound
by Eli Lilly
Class
GLP-1 + GIP dual receptor agonist
Approved for
Chronic weight management (BMI ≥30 or ≥27 with comorbidity)
Avg weight loss
~20–22%
Trial data
SURMOUNT trials
Same drug as Mounjaro, FDA-approved for weight loss. Currently shows the highest average weight loss of any approved medication.
Note: Newest of the four. Also approved in 2024 for obstructive sleep apnea in adults with obesity. Growing evidence base.
Side-by-side comparison
Average weight loss figures are from respective registration trials at highest approved doses. Individual results vary.
Frequently asked questions
What is the difference between Ozempic and Wegovy?
Ozempic and Wegovy contain the same active ingredient (semaglutide) but at different doses and with different FDA approvals. Ozempic is approved for type 2 diabetes management at up to 2mg. Wegovy is approved specifically for chronic weight management at a higher dose of 2.4mg.
What is the difference between Mounjaro and Zepbound?
Mounjaro and Zepbound contain the same active ingredient (tirzepatide) but with different FDA approvals. Mounjaro is approved for type 2 diabetes. Zepbound is approved for chronic weight management. Both use a dual GLP-1 + GIP mechanism that appears to produce greater weight loss than semaglutide alone.
Which GLP-1 medication causes the most weight loss?
In clinical trials, Zepbound and Mounjaro (tirzepatide) showed the highest average weight loss at approximately 20–22% of body weight at the highest doses. Wegovy and Ozempic (semaglutide) showed approximately 15–17% average weight loss. Individual results vary significantly.
Can I take Ozempic for weight loss if I don't have diabetes?
Ozempic is FDA-approved for type 2 diabetes, not weight loss. However, Wegovy — which contains the same active ingredient (semaglutide) at a higher dose — is FDA-approved for weight management. Many prescribers prescribe Ozempic off-label for weight loss, but insurance coverage differs.
You've started treatment — now what?
Whichever medication or care plan you're on, the aftercare challenges can be similar. Browse our practical guides for the most common ones.