Quick Summary

Mounjaro (dual-action) shows slightly better weight loss results (15-20%) than Wegovy (12-15%), but both are highly effective. Mounjaro targets GLP-1 and GIP receptors; Wegovy targets only GLP-1. Both have similar side effects. Our pharmacist helps determine which is right for you.

Mounjaro vs Wegovy: Treatment Comparison

Medical Review: Reviewed by registered pharmacist. Last Updated: February 2026. Location: Glasgow, Scotland.

Side-by-Side Comparison

Feature	Mounjaro	Wegovy
Active Ingredient	Tirzepatide	Semaglutide
Mechanism	Dual-action (GLP-1 + GIP)	GLP-1 only
Average Weight Loss	15-20% body weight	12-15% body weight
Administration	Weekly injection	Weekly injection
Side Effects	Similar (GI symptoms)	Similar (GI symptoms)
FDA Approved	Yes	Yes

Key Differences

Mechanism of Action

Mounjaro (Tirzepatide): Targets both GLP-1 and GIP receptors, providing dual-action appetite suppression and metabolic benefits.

Wegovy (Semaglutide): Targets only the GLP-1 receptor, providing effective appetite suppression through a single mechanism.

Effectiveness

Clinical trials show:

Mounjaro: Average weight loss of 15-20% body weight over 72 weeks
Wegovy: Average weight loss of 12-15% body weight over 68 weeks

While Mounjaro shows slightly better results on average, individual responses vary. Both medications are highly effective for weight loss.

Side Effects

Both medications have similar side effect profiles:

Nausea, vomiting, diarrhoea, constipation
Abdominal pain
Fatigue, dizziness

Side effects are usually mild and temporary, occurring most often when starting treatment or increasing dosage.

Which Treatment is Right for You?

The best treatment depends on several factors:

Your medical history and current medications
Your weight loss goals
Your response to treatment
Cost and availability

Our registered pharmacist will help determine which medication is most suitable for you during your consultation. Learn more about Mounjaro or Wegovy.

Frequently Asked Questions

Which is more effective: Mounjaro or Wegovy?

Clinical trials show Mounjaro produces slightly better weight loss results (15-20% body weight) compared to Wegovy (12-15% body weight). However, individual responses vary, and both are highly effective treatments.

What is the main difference between Mounjaro and Wegovy?

Mounjaro targets both GLP-1 and GIP receptors (dual-action), while Wegovy targets only the GLP-1 receptor. This dual-action mechanism may contribute to Mounjaro's superior results.

Do they have different side effects?

Both medications have similar side effect profiles, primarily gastrointestinal symptoms like nausea, vomiting, and diarrhoea. Side effects are usually mild and temporary.

Can I switch from Wegovy to Mounjaro?

Yes, switching between medications is possible under pharmacist supervision. Our pharmacist can assess whether switching would be beneficial for you.

Which treatment is right for me?

The best treatment depends on your individual circumstances, medical history, and goals. Our registered pharmacist will help determine which medication is most suitable during your consultation.