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Semaglutide: Frequently Asked Questions

FM

Reviewed by Fat Man in the Arena · Updated March 2026

Not medical advice. These answers are for educational purposes based on published research. Full disclaimer.

How much weight can you lose on semaglutide?

In the STEP 1 clinical trial published in the New England Journal of Medicine in 2021, participants taking 2.4 mg semaglutide weekly lost an average of 14.9% of their body weight over 68 weeks. About one-third of participants achieved 20% or greater weight loss compared to placebo.

What are the most common side effects of semaglutide?

The most common side effects are gastrointestinal: nausea, vomiting, diarrhea, and constipation. These typically occur during dose escalation and improve over time. Starting at a low dose and titrating slowly over 16-20 weeks helps minimize these effects significantly.

Is semaglutide FDA approved for weight loss?

Yes. Semaglutide is FDA-approved for chronic weight management under the brand name Wegovy at 2.4 mg weekly injection. In December 2025, the FDA also approved an oral formulation of Wegovy (25 mg tablet), making it the first oral GLP-1 for weight management.

Do you regain weight after stopping semaglutide?

Research suggests most people regain a significant portion of lost weight after discontinuing semaglutide. The STEP 1 extension trial showed participants regained about two-thirds of their lost weight within one year of stopping treatment. Lifestyle changes during treatment may help mitigate regain.

Sources

  • Once-Weekly Semaglutide in Adults with Overweight or Obesity (STEP 1)New England Journal of Medicine (2021) [PubMed]
  • Two-Year Effects of Semaglutide in Adults with Overweight or Obesity (STEP 5)Nature Medicine (2022) [PubMed]

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