Across the Phase 2 and Phase 3 orforglipron trials, the most common adverse events were gastrointestinal: nausea, vomiting, diarrhea, and constipation. They were generally mild to moderate and tended to track the dose, showing up most during escalation, a pattern consistent with other GLP-1 receptor agonists.[1][2]
Reviewed for accuracy · Last reviewed July 8, 2026Discontinuation for adverse events was higher on orforglipron than placebo (roughly 10 – 17% across Phase 2 dose cohorts and about 5 – 10% across ATTAIN-1 dose groups), driven mainly by gastrointestinal effects. GLP-1 receptor agonists as a class carry a labeled warning about thyroid C-cell tumors seen in rodents, so check the current label for the full safety profile.
Gastrointestinal effects most often appear right after a dose step-up. Escalating slowly and holding a dose steady before the next increase are commonly discussed ways to limit nausea, though individual experience varies.
This page is an independent educational reference and is not medical advice. Talk to a doctor before starting or adjusting any compound.