Here’s a comprehensive overview of the side effects of Semaglutide (Wegovy) — drawing on clinical trials, drug labels, and real-world data to help you understand what to expect:
1. Common Side Effects
Typically mild to moderate and often temporary as your body adjusts:
- Gastrointestinal (GI): The most frequently reported symptoms:
- Nausea (up to ~44%), vomiting, diarrhea, constipation, abdominal pain, bloating, acid reflux, indigestion, belching, gas
NCBILloydsPharmacy Online Doctoreudoctor.orgReddit
- Nausea (up to ~44%), vomiting, diarrhea, constipation, abdominal pain, bloating, acid reflux, indigestion, belching, gas
- Other general symptoms:
- Headache, fatigue/tiredness, dizziness, burping, upset stomach, nasal or throat irritation (common cold-like symptoms)
LloydsPharmacy Online DoctorDrugs.comWebMD
- Headache, fatigue/tiredness, dizziness, burping, upset stomach, nasal or throat irritation (common cold-like symptoms)
2. Less Common but Clinically Important Side Effects
These are less frequent but warrant attention and possibly medical follow-up:
- Hypoglycemia (low blood sugar): Particularly in people with type 2 diabetes or those using insulin/sulfonylureas
eudoctor.orgWegovyWebMD - Pancreatitis: Inflammation of the pancreas—seek immediate help if you experience persistent upper abdominal pain that radiates to your back
WegovymedinoWebMD - Gallbladder issues: Gallstones, cholecystitis, or related symptoms (e.g., upper abdominal pain, jaundice)
eudoctor.orgWegovymedino - Kidney problems/dehydration: Vomiting, diarrhea, or nausea may lead to dehydration and worsening kidney function
WegovyWebMD - Severe allergic reactions: Rare but serious—swelling, rash, facial/lip/throat swelling, difficulty breathing require immediate attention
eudoctor.orgWegovyWebMDCleveland Clinic - Increased heart rate (tachycardia): Mild but may be noticeable as a resting heart rate increase
eudoctor.orgWegovyWebMD - Vision changes: Especially in those with diabetic retinopathy—monitor for visual disturbances
WegovyWebMD - Mood changes, depression, suicidal thoughts: Uncommon but serious—report any new or worsening mental health symptoms promptly
WegovyWebMDCleveland Clinic
3. Warning: Thyroid Tumor Risk
- Thyroid C‑cell Tumors (rodent studies): Semaglutide caused thyroid tumors in rodents. Human relevance is unknown, but the risk remains a concern.
- Contraindications: Those with a personal or family history of medullary thyroid carcinoma or MEN 2 syndrome should not take Wegovy
Drugs.comWegovyeudoctor.org
4. Rare or Emerging Concerns
Newer findings or very rare side effects being monitored:
- Eye-related issues:
- Hair loss (alopecia): Semaglutide users showed a ~50% higher risk compared to some other weight-loss medications. Overall incidence in trials was around 2–2.5%
New York PostWikipedia
5. Summary Table
| Side Effect Category | Examples & Notes |
|---|---|
| Common | Nausea, vomiting, diarrhea, constipation, headache, fatigue |
| Less Common/Serious | Hypoglycemia, pancreatitis, gallstones, kidney effects, allergic reaction, tachycardia, vision changes, mental health |
| Warnings / Contraindications | Thyroid tumor risk (rodent studies); avoid with MTC or MEN 2 |
| Rare/Emerging | NAION (eye), macular degeneration, hair loss |
Final Thoughts
Wegovy (Semaglutide) is an effective weight-management medication, but like any treatment, it carries potential side effects—mostly digestive issues at first, which often improve with dose adjustments. Serious effects are rare but can be severe, underscoring the importance of medical supervision throughout your treatment.
If you’d like, I can help you plan for side effect management strategies, like dietary tweaks, hydration, or how to taper doses to minimize discomfort. Just let me know!
