How Long Does Semaglutide Take to Work for Weight Loss?
When you start a new weekly shot, it is natural to want to know when you will see a change. With semaglutide, the answer comes in stages, because the dose starts low and builds up over several months.
So how long does semaglutide take to work? It slows how fast the stomach empties and can lower appetite.[1] Weight loss then builds over months. In one large trial, adults lost an average of 10.6% of their body weight in the first 20 weeks.[2] In another, the average loss after 68 weeks was 14.9%.[3] These are averages from trials, not a promise for any one person.
The First Weeks
Treatment starts at a low dose. The dose is usually raised after 4 weeks, and then in further steps.[1] Starting low gives your body time to adjust. Stomach side effects, such as nausea and diarrhea, are the most common. They are usually short-lived and mild to moderate.[3]
Weight loss builds gradually while the dose is still going up. By week 20 in one trial, the average loss had reached 10.6%.[2]
Over the First Year
| Weight lost after 68 weeks | People on semaglutide | People on a placebo |
|---|---|---|
| 5% or more | 86% | 32% |
| 10% or more | 69% | 12% |
| 15% or more | 51% | 5% |
These figures come from a trial of nearly 2,000 adults with obesity, or adults who were overweight with a weight-related health problem. None had diabetes. Everyone in the trial, including the placebo (dummy shot) group, also had help with diet and physical activity.[3]
About half of the people on semaglutide lost 15% or more of their body weight. For someone who starts at 200 pounds, 15% is 30 pounds. Others lost less, and a smaller group lost under 5%.[3]
See If Semaglutide Is Right for You
Complete a short online questionnaire. A licensed clinician reviews your health history before prescribing.
What Shapes Your Own Results
Results vary from person to person. These three things shape them, and two are in your control:
- Time. The dose goes up in steps, and weight loss builds over months.[1][2]
- Diet and activity. The NIH notes that weight loss medicines work best alongside healthy eating and physical activity.[4]
- Taking it every week. Semaglutide is a once-weekly shot. If you miss a dose for weight loss, take it within 2 days, or skip it and take the next one on time.[1]
The NIH also gives a checkpoint. If you have not lost at least 5% of your weight after 12 weeks on the full dose, your prescriber will probably advise you to stop.[4]
How These Results Apply to Compounded Semaglutide
The trials above did not test compounded semaglutide. Compounded semaglutide is prepared by a licensed pharmacy for each patient. Because it is prepared for an individual, it is not FDA-approved,[5] so the trial results are the best guide to what the medicine can do, rather than a measure of any one compounded product.
FAQ
How much weight can you lose on semaglutide?
In the main trial, the average was 14.9% of body weight after 68 weeks, compared with 2.4% on a placebo. About half lost 15% or more.[3] Your own result may be higher or lower.
When will I see results on semaglutide?
Weight loss builds over months as the dose goes up. In one trial, the average loss was 10.6% by week 20.[2]
Where can I book an online GLP-1 consultation with a doctor?
With Starfish.com, there is no appointment to book. You complete an online questionnaire, and a licensed clinician reviews it. If treatment is appropriate, you get a prescription, usually within 1 to 2 hours. Your medication is then mailed to you from the pharmacy.
What happens if I stop semaglutide?
You will probably regain some weight,[4] but many people keep part of their loss. In one trial, people regained about two-thirds of the weight they had lost within a year of stopping, yet on average they still weighed 5.6% less than when they started.[6] Staying on treatment helps hold on to results: in another trial, people who kept taking semaglutide lost a further 7.9%.[2] Healthy eating and physical activity help too, and the NIH notes that weight loss medicines work best alongside them.[4]
Start Your Semaglutide Request
A licensed clinician reviews your answers and, if treatment is right for you, issues a prescription within 1 to 2 hours. Your medication is mailed to you.
References
- U.S. National Library of Medicine, MedlinePlus. “Semaglutide Injection.” https://medlineplus.gov/druginfo/meds/a618008.html
- Rubino D, et al. “Effect of Continued Weekly Subcutaneous Semaglutide vs Placebo on Weight Loss Maintenance in Adults With Overweight or Obesity: The STEP 4 Randomized Clinical Trial.” JAMA, 2021. https://doi.org/10.1001/jama.2021.3224
- Wilding JPH, et al. “Once-Weekly Semaglutide in Adults with Overweight or Obesity.” New England Journal of Medicine, 2021. https://doi.org/10.1056/NEJMoa2032183
- National Institute of Diabetes and Digestive and Kidney Diseases. “Prescription Medications to Treat Overweight & Obesity.” https://www.niddk.nih.gov/health-information/weight-management/prescription-medications-treat-overweight-obesity
- U.S. Food and Drug Administration. “Compounding and the FDA: Questions and Answers.” https://www.fda.gov/drugs/human-drug-compounding/compounding-and-fda-questions-and-answers
- Wilding JPH, et al. “Weight regain and cardiometabolic effects after withdrawal of semaglutide: The STEP 1 trial extension.” Diabetes, Obesity and Metabolism, 2022. https://doi.org/10.1111/dom.14725
