GLP-1 Medication Comparison: Mounjaro vs Ozempic vs Wegovy

A side-by-side comparison of the most popular GLP-1 and GIP agonist medications for weight loss and diabetes management, including dosing, mechanism, and clinical trial results.

What is the difference between Mounjaro and Ozempic?

Mounjaro (tirzepatide) targets both GIP and GLP-1 receptors, while Ozempic (semaglutide) targets only GLP-1. In clinical trials, Mounjaro showed greater average weight loss (~22.5% vs ~15%). Mounjaro comes in 6 strengths (2.5-15mg), while Ozempic maxes out at 2mg.

Medication Comparison Table

Compare the key characteristics of the five most prescribed weight loss and diabetes injectable medications:

Medication Active Ingredient Mechanism Approved For Frequency
Mounjaro Tirzepatide Dual GIP/GLP-1 Type 2 diabetes Weekly
Zepbound Tirzepatide Dual GIP/GLP-1 Weight management Weekly
Ozempic Semaglutide GLP-1 only Type 2 diabetes Weekly
Wegovy Semaglutide GLP-1 only Weight management Weekly
Saxenda Liraglutide GLP-1 only Weight management Daily

Dosing Comparison

Each medication has its own titration schedule and dose range. Starting doses are low to minimize side effects, and are gradually increased over weeks or months.

Medication Starting Dose Max Dose Delivery Device
Mounjaro 2.5 mg 15 mg KwikPen (multi-dose, click-based)
Zepbound 2.5 mg 15 mg Prefilled pen
Ozempic 0.25 mg 2 mg Prefilled pen
Wegovy 0.25 mg 2.4 mg Prefilled pen
Saxenda 0.6 mg 3 mg Prefilled pen

Dual vs Single Receptor Agonists

The key distinction between these medications is whether they target one or two hormone receptors. This affects both efficacy and how the body responds to treatment.

Dual GIP/GLP-1 Agonist (Tirzepatide)

Targets both GIP and GLP-1 receptors for potentially greater metabolic effects:

  • • Greater average weight loss in clinical trials
  • • Enhanced insulin sensitivity through dual pathway
  • • Available as Mounjaro (diabetes) and Zepbound (weight loss)

GLP-1 Only Agonist (Semaglutide, Liraglutide)

Targets the GLP-1 receptor for proven appetite suppression and metabolic benefits:

  • • Well-established safety profile with over 10 years of data
  • • Available in multiple formulations (weekly and daily)
  • • Ozempic, Wegovy, Rybelsus (oral), Saxenda

Which GLP-1 medication causes the most weight loss?

Tirzepatide (Mounjaro/Zepbound) has shown the greatest weight loss in clinical trials, with an average of 22.5% body weight loss at the highest dose (15mg). Semaglutide (Wegovy) averages ~15%, and liraglutide (Saxenda) averages ~8%. Individual results vary.

Weight Loss Results from Clinical Trials

Average body weight reduction at the highest approved dose, as reported in major clinical trials:

~22.5%

Mounjaro (15 mg)

SURMOUNT-1 trial, 72 weeks

~15%

Wegovy (2.4 mg)

STEP 1 trial, 68 weeks

~12%

Ozempic (2 mg)

SUSTAIN trials, 40-56 weeks

~8%

Saxenda (3 mg)

SCALE trial, 56 weeks

Results are averages from clinical trials with diet and exercise. Individual results vary significantly. Always consult your healthcare provider.

Frequently Asked Questions

Can I switch from Ozempic to Mounjaro?
Yes, switching between GLP-1 medications is possible under medical supervision. Your doctor will typically start you at a lower dose of the new medication and titrate up. There may be a brief adjustment period.
Is Mounjaro the same as Zepbound?
Yes, both contain tirzepatide and are made by Eli Lilly. Mounjaro is approved for type 2 diabetes, while Zepbound is approved specifically for weight management. The dosing strengths and injection pen are the same.
Which has fewer side effects, Mounjaro or Ozempic?
Both medications share similar gastrointestinal side effects (nausea, diarrhea, constipation). Clinical trial data suggests comparable side effect rates. Individual tolerance varies, and starting at a low dose with gradual titration helps minimize side effects for both.
Do GLP-1 medications work without diet and exercise?
GLP-1 medications reduce weight even without major lifestyle changes, but results are significantly better when combined with a healthy diet and regular exercise. Clinical trials included diet and exercise counseling for all participants.

Related Articles

Using a Mounjaro KwikPen?

Calculate exactly how many clicks you need for your dose, including custom dose splitting for any pen strength.

Open Dose Calculator