Retatrutide: Side Effects & Safety

Part of the Retatrutide Complete Guide

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Common Side Effects (Phase 2 Data)

  • Nausea (26–45%): Most common, worst during dose titration
  • Diarrhea (15–22%): Usually mild to moderate, transient
  • Vomiting (8–18%): More common at higher doses
  • Decreased appetite (10–15%): Pharmacological effect
  • Constipation (8–12%): From slowed gastric motility
  • Injection site reactions (5–10%)

Discontinuation rates were 5–10% across dose groups. No serious safety signals were identified in Phase 2. Larger Phase 3 trials will provide more comprehensive data.

GLP-1 Class Risks

As with all GLP-1 agonists, theoretical concerns include pancreatitis and thyroid C-cell tumors (observed in rodents). These risks will be further characterized in Phase 3. For the complete overview, see the retatrutide complete guide.

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Peptides Insider Editorial Team

Our content is reviewed for accuracy and grounded in peer-reviewed research where available. We do not provide medical advice. Always consult a qualified healthcare professional.