Common effects
Nausea is the most frequent adverse event, followed by vomiting, diarrhea, and constipation. These are dose-related and typically peak during dose escalation; gradual titration is the labeled mitigation.
Boxed-mention warnings
Contraindication in personal/family history of medullary thyroid carcinoma or MEN2, based on rodent C-cell findings. Labeled warnings include pancreatitis, gallbladder disease (including cholelithiasis, particularly with rapid weight loss), acute kidney injury secondary to dehydration from GI effects, and retinopathy complications in patients with existing diabetic retinopathy.
Rare and monitored
Gastroparesis reports, aspiration risk under anesthesia (relevant for procedural fasting guidance), and hypersensitivity reactions appear in surveillance literature and label updates.
What the label means
A labeled warning is not a prediction — it is a documented risk that clinicians weigh per patient. This page reports the label; it does not substitute for it.
References
- Wilding JPH, et al. Once-Weekly Semaglutide in Adults with Overweight or Obesity (STEP 1). N Engl J Med 2021. [source]
- Drucker DJ. Mechanisms of Action and Therapeutic Application of Glucagon-Like Peptide-1. Cell Metab 2018. [source]
- ClinicalTrials.gov — registered semaglutide studies. [source]
Evidence tier: Approved medicine · Last reviewed: 2026-09-05 · Sources cited below.