Peptides
Semaglutide
What is it?
Semaglutide is a medicine that acts on the GLP-1 receptor. Different prescription products are approved for different uses, including type 2 diabetes and weight management. This page focuses on adult weight management with Wegovy; its injection and tablets have different schedules. [1]
How does it work?
It helps regulate appetite and food intake and also affects glucose-dependent insulin signaling. Weight loss comes from the treatment together with sustained changes in eating and activity, not from a direct muscle-building effect. [1]
What have weight-loss studies found?
In STEP 1, 1,961 adults with obesity or overweight plus a related condition, without diabetes, were assigned to weekly 2.4 mg semaglutide or placebo alongside lifestyle support. At 68 weeks, mean weight change was 14.9% loss versus 2.4% loss on placebo. Gastrointestinal symptoms were more common with semaglutide. This is substantial direct human evidence, though individual results vary. [2]
For people with obesity and established cardiovascular disease, another large randomized trial found fewer major cardiovascular events with semaglutide than placebo. That does not mean every person using it for weight loss has the same risk reduction. [3]
What should you know before considering it?
The prescription label carries a boxed warning about thyroid C-cell tumors in rodents and a contraindication for people with personal or family history of medullary thyroid carcinoma or MEN2. Nausea, vomiting, gallbladder problems, pancreatitis concerns, and dehydration require appropriate screening and follow-up. [1]
PRESCRIPTION START
How much?
FORM & SCHEDULE
What it refers to
once weekly for 4 weeks, then gradual increases
A prescriber chooses the product and schedule. The oral tablets have a different daily dose. Thyroid-cancer family history and other warnings need screening.
0.25 mg — Wegovy injection once weekly for the first four weeks, then gradual escalation. For adult weight reduction, 2.4 mg weekly is the recommended maintenance dose; 1.7 mg may be used, and the current label allows 7.2 mg for selected adults when more reduction is clinically indicated after tolerating 2.4 mg. [1]
Read detailed dosing notes
This is prescription-label context, not a personal dosing plan. Wegovy tablets use a separate daily schedule and cannot be exchanged milligram-for-milligram with injections. [1]
Sources & further reading
- FDA/DailyMed (2026). Wegovy prescribing information (opens in a new tab)dailymed.nlm.nih.gov
- Wilding et al. (2021). Once-weekly semaglutide in adults with overweight or obesity (opens in a new tab)www.nejm.org
- Lincoff et al. (2023). Semaglutide and cardiovascular outcomes in obesity without diabetes (opens in a new tab)www.nejm.org