Weight Loss Peptides Compared: Retatrutide vs Tirzepatide vs Semaglutide

The Big Three

The weight loss peptide landscape has been transformed by three compounds: Semaglutide (Ozempic/Wegovy), Tirzepatide (Mounjaro), and the emerging Retatrutide. Here's how they compare.

Mechanism Comparison

CompoundReceptorsMechanism

|----------|-----------|-----------|

SemaglutideGLP-1Single agonist TirzepatideGLP-1 + GIPDual agonist RetatrutideGLP-1 + GIP + GlucagonTriple agonist

Efficacy

Average weight loss at 48-72 weeks:

Semaglutide: ~15% body weight

Tirzepatide: ~20% body weight

Retatrutide: ~24% body weight (Phase 2 data)

Side Effect Profile

All three share similar GI side effects (nausea, vomiting, diarrhea) during dose titration. Retatrutide may have slightly higher early nausea due to the glucagon component.

Dosing Frequency

All are weekly injections, making them equally convenient.

Cost Considerations

Retatrutide is currently the most cost-effective option when sourced from compounding pharmacies, as brand-name versions have not yet reached market.

Who Should Choose What?

Mild weight loss needs (< 20lbs): Semaglutide

Moderate needs + insulin resistance: Tirzepatide

Maximum results + metabolic optimization: Retatrutide

Conclusion

Retatrutide offers the highest efficacy ceiling. For most users seeking significant weight loss, it represents the best value and most advanced option currently available.