GLP-1 medicines, explained
Forms, trial results, and the questions to bring to a prescriber
Key Takeaway
There is no single GLP-1 form or schedule. Wegovy has weekly injections and daily tablets; Zepbound is a weekly injection. Trial averages describe specific products, doses, and participants, not the result or right treatment for one person.
A product name tells you more than the phrase “GLP-1.” Start with the exact medicine, form, approved use, and current patient instructions. Here is what the FDA labels and two named trials can answer, and what they cannot.
What Is GLP-1?
GLP-1 is a hormone involved in appetite and blood-sugar regulation. Semaglutide activates its receptor. Tirzepatide acts at both GLP-1 and GIP receptors. The FDA labels describe reduced food intake as a likely part of their weight-loss effect; that mechanism alone does not predict an individual result. Wegovy label · Zepbound label
The Main Players
Semaglutide comes in different products and forms. Wegovy includes weekly injections, a 7.2 mg Wegovy HD injection for eligible adults, and daily tablets. Indications, starting doses, missed-dose instructions and storage depend on the exact product. A dose or rule for Ozempic cannot automatically be applied to Wegovy.
The form and directions belong to a finished product, not to the ingredient name alone.
| Product | Form and schedule in its label |
|---|---|
| Wegovy (semaglutide) | Weekly injection or daily tablet. The exact directions differ by form. FDA label |
| Zepbound (tirzepatide) | Weekly injection. Device and handling instructions depend on the presentation. FDA label |
Ozempic, Mounjaro, Rybelsus, and other familiar names have their own records. Do not borrow Wegovy or Zepbound directions for another product. Find the exact FDA drug record.
How Well Do They Work?
These are results from named research groups and treatment regimens, not a range to expect from every GLP-1 product.
| Study | Result and limit |
|---|---|
| STEP 1 | Among 1,961 adults without diabetes meeting the trial criteria, mean weight change at 68 weeks was 14.9% lower with weekly injected semaglutide 2.4 mg plus lifestyle intervention, versus 2.4% lower with placebo plus lifestyle intervention. This does not measure Wegovy tablets or predict a personal result. Primary trial |
| SURMOUNT-5 | In SURMOUNT-5, 751 adults with obesity without type 2 diabetes were assigned maximum tolerated weekly injections of tirzepatide (10 or 15 mg) or semaglutide (1.7 or 2.4 mg). Mean weight loss at 72 weeks was 20.2% versus 13.7%. This result does not compare oral semaglutide, Wegovy HD 7.2 mg, every dose or people with diabetes, and does not predict an individual's result. Primary trial |
Side Effects and Safety
The Wegovy and Zepbound labels list nausea, vomiting, diarrhea, constipation, and abdominal symptoms among common adverse reactions. Both also contain warnings about serious problems, including pancreatitis, gallbladder disease, dehydration-related kidney injury, and severe allergic reactions. The frequency and instructions differ by exact product and studied group. Wegovy label · Zepbound label
Use the side-effects guide for a short symptom-and-action checklist, then check your own Medication Guide and ask the prescriber or pharmacist about your situation.
What about lean mass?
Weight change on a scale does not say how much fat or lean tissue changed. Lean mass is not a measurement of muscle alone. The product labels describe more fat-mass than lean-mass loss in their clinical findings; neither provides a personal muscle-loss estimate. Ask the care team how they will assess nutrition, strength, and function during treatment. Wegovy label · Zepbound label
What Happens When You Stop?
In an exploratory follow-up of 327 STEP 1 participants who completed the 68-week trial, the group previously using weekly injected semaglutide 2.4 mg regained about two-thirds of its prior weight loss over one year after the medicine and structured lifestyle intervention stopped. That is a group average for this treatment and follow-up design, not a prediction for you or every GLP-1 product. Primary STEP 1 extension
Before starting, stopping, or switching a prescription, ask the care team what follow-up, costs, and alternatives would look like for the exact product. For offer terms, compare GLP-1 options, check insurance help or self-pay options, and use the full-cost and coverage guide.
Who Should Consider GLP-1 Medicines?
Wegovy and Zepbound have product-specific FDA indications for weight reduction in adults with obesity or overweight plus a weight-related condition. Their labels also have contraindications, including a personal or family history of medullary thyroid cancer or MEN 2. Those facts are a reason to review the exact label and health history with a prescriber, not a self-eligibility test or a recommendation for one product. Wegovy label · Zepbound label
Sources and Scope
We checked these primary records on October 21, 2026. The trial results apply to the stated participants and regimens. FDA labels govern the named finished products and can change; check the current record before making a treatment decision.
- FDA: Wegovy injection and tablet prescribing information, checked 2026-10-21
- FDA: Zepbound prescribing information, checked 2026-10-21
- STEP 1 randomized trial, PMID 33567185, DOI 10.1056/NEJMoa2032183, checked 2026-10-21
- STEP 1 extension, PMID 35441470, DOI 10.1111/dom.14725, checked 2026-10-21
- SURMOUNT-5 randomized trial, PMID 40353578, DOI 10.1056/NEJMoa2416394, checked 2026-10-21
- FDA: Find information about a drug, checked 2026-10-21
Frequently Asked Questions
How much weight can you lose on GLP-1 medications?
In SURMOUNT-5, 751 adults with obesity without type 2 diabetes were assigned maximum tolerated weekly injections of tirzepatide (10 or 15 mg) or semaglutide (1.7 or 2.4 mg). Mean weight loss at 72 weeks was 20.2% versus 13.7%. This result does not compare oral semaglutide, Wegovy HD 7.2 mg, every dose or people with diabetes, and does not predict an individual's result.
Are all GLP-1 medicines weekly injections?
No. The FDA Wegovy label includes weekly injections and daily tablets. Zepbound is a weekly injection. Check the label for your exact product and form.
Is the result in a trial what I should expect?
No. The results here come from specific participants, products, doses, and time periods. A trial average cannot predict an individual result.
Can I use another semaglutide product the same way as Wegovy?
Do not assume that. Different finished products and forms have their own FDA labels and instructions. Ask the prescriber or pharmacist about the exact product.
How do I know which product fits me?
Review the exact FDA label, health history, other medicines, and treatment goals with a licensed prescriber. This guide does not determine eligibility or recommend a prescription.