What are the side effects of Wegovy (semaglutide)?

Side Effects of Wegovy (Semaglutide)

Wegovy (semaglutide) commonly causes gastrointestinal side effects and has a 38% higher risk of serious adverse events compared to placebo, with specific concerns including gallbladder disease, pancreatitis, and potential cardiovascular complications. 1

Common Gastrointestinal Side Effects

• Nausea, vomiting, diarrhea, constipation, and abdominal pain are the most frequent adverse effects of semaglutide 1, 2
• These gastrointestinal effects are typically dose-dependent and more pronounced during initial treatment or dose escalation 2, 3
• Most gastrointestinal side effects are mild-to-moderate in severity (98.1% of cases) and transient in nature 3
• Gastrointestinal events may lead to treatment discontinuation in approximately 4.5% of patients compared to 0.8% with placebo 4, 3
• Delayed gastric emptying is a known effect that may contribute to gastrointestinal symptoms and potentially affect absorption of other medications 2, 5

Serious Adverse Events

• Clinical trials show a 38% higher risk of serious adverse events with semaglutide compared to placebo 1, 2
• Specific serious adverse events reported include:
  • Pancreatitis 1, 2, 6
  • Gallbladder disease including cholelithiasis and cholecystitis 1, 2
  • Acute myocardial infarction 1
  • Gastroenteritis 1
  • Potential for acute kidney injury, particularly in patients with pre-existing kidney disease 2

Contraindications and Special Considerations

• Semaglutide is contraindicated in patients with:
  • Personal or family history of medullary thyroid cancer 1, 2
  • Multiple endocrine neoplasia syndrome type 2 1, 2
• Increased risk of hypoglycemia when used with insulin, sulfonylureas, or glinides 1, 2
• Not recommended in patients with clinically meaningful gastroparesis 1
• Caution advised in patients with prior gastric surgery, including bariatric surgery 1
• Diabetic retinopathy complications have been reported with injectable semaglutide 1, 7

Management of Side Effects

• Gradual dose titration is recommended to minimize gastrointestinal side effects 2
• Gastrointestinal side effects typically occur during or shortly after dose escalation 3
• Most gastrointestinal adverse events resolve with time even with continued treatment 4, 3
• Weight loss with semaglutide appears to be largely independent of gastrointestinal side effects, with similar weight loss observed in patients with and without these adverse events 3

Cardiovascular Considerations

• In 2024, Wegovy was approved by the FDA to reduce the risk of cardiovascular death, heart attack, and stroke in adults with obesity or overweight and cardiovascular disease 1
• In a large trial with over 17,600 participants, major cardiovascular events occurred in 6.5% of those treated with Wegovy, compared with 8% in the placebo group 1
• Semaglutide has been shown to improve cardiovascular risk factors including cholesterol profiles, blood pressure, and inflammatory markers 1

Other Potential Side Effects

• Injection site reactions may occur 1
• Insomnia has been documented as a potential side effect 2
• Risk of suicidal ideation has been reported in some cases 1
• Potential for severe allergic reactions 7

Monitoring Recommendations

• Monitor for gastrointestinal symptoms, particularly during dose escalation 2
• Monitor for signs of pancreatitis (persistent severe abdominal pain) 2, 6
• Monitor for gallbladder disease 2
• Regular monitoring of renal function is advised, particularly in those with pre-existing kidney disease 2
• Monitor for hypoglycemia when used with other glucose-lowering medications 2