Semaglutide Side Effects
FDA Approved
FM
Reviewed by Fat Man in the Arena · Updated March 2026
Important safety information. This page covers known and reported side effects of Semaglutide. This is not a complete list. Always discuss potential risks with your healthcare provider before starting any peptide protocol. Full medical disclaimer.
Known side effects
The following side effects have been reported in clinical trials for Semaglutide:
- Nausea (most common, typically improves over time)
- Vomiting
- Diarrhea
- Constipation
- Abdominal pain
- Headache
- Rare: pancreatitis, gallbladder issues
- Potential muscle mass loss alongside fat loss
Severity and frequency
Clinical trial data provides specific frequency data for Semaglutide side effects. Most common side effects are mild to moderate and often improve with continued use or dose adjustment.
When to seek medical attention
Contact your healthcare provider immediately if you experience:
- Severe or persistent symptoms that do not improve
- Signs of an allergic reaction (rash, swelling, difficulty breathing)
- Severe abdominal pain
- Changes in vision or neurological symptoms
- Any symptom that concerns you
Risk factors
Side effect risk may be higher in certain populations. Discuss your complete medical history with your doctor, including:
- Pre-existing medical conditions
- Current medications (drug interactions)
- Pregnancy or plans to become pregnant
- History of allergic reactions to peptides or similar compounds
Research references
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