Oral Semaglutide GLP-1 has a similar side effect profile to the injectable form, because the active ingredient is the same. The most common side effects are gastrointestinal.
Common side effects:
- Nausea, particularly in the first 2 to 4 weeks.
- Vomiting less common than nausea, but possible.
- Diarrhea or constipation.
- Headache.
- Abdominal pain or discomfort.
- Decreased appetite.
Most of these are mild to moderate and tend to improve over the first few weeks as your body adjusts.
Less common side effects:
- Fatigue.
- Dizziness or lightheadedness.
- Low blood sugar (hypoglycemia) particularly when combined with other diabetes medications.
Serious side effects requiring immediate attention:
- Severe abdominal pain that won't resolve particularly with vomiting (possible pancreatitis).
- Signs of an allergic reaction facial swelling, difficulty breathing, severe rash.
- Persistent vomiting that prevents fluid intake.
- Possible thyroid-related symptoms a lump in the neck, hoarseness, trouble swallowing.
What to do:
- Take the medication consistently. Sublingual administration matters — see "How is Buccal Semaglutide taken?" for proper technique.
- Stay hydrated, particularly during the first weeks.
- Eat smaller, more frequent meals to reduce nausea.
- Message your clinician if side effects are bothersome or persistent past the adjustment window.
- Call 911 or go to an emergency room for serious side effects.
Your clinician can adjust your dose or titration schedule if side effects are interfering with your daily life.