Definition
Semaglutide is a GLP-1 receptor agonist. It is the active ingredient in Ozempic and Wegovy injections and in Rybelsus, Ozempic and Wegovy tablets. Injections are taken once a week. Tablets are taken once a day.
Semaglutide is 94% similar to the GLP-1 hormone your gut makes. It binds to albumin in the blood and resists the enzyme DPP-4, so its half-life is about one week. The Wegovy label says it stays in the body for about 5 to 7 weeks after the last dose. Ozempic injection is approved for type 2 diabetes and to lower heart and kidney risks in people with type 2 diabetes. Wegovy is approved for weight reduction and heart risk reduction, and the injection also for a liver condition called MASH. Rybelsus and Ozempic tablets are approved for type 2 diabetes. For the tablets, see oral semaglutide.
Wegovy injection starts at 0.25 mg once a week and goes up every 4 weeks (0.5, 1 and 1.7 mg) to a usual maintenance dose of 2.4 mg, with 7.2 mg (Wegovy HD) as an option for some adults. Ozempic goes up to 2 mg. In the Wegovy label, nausea affected 44% of adults on 2.4 mg vs 16% on placebo, and constipation 24% vs 11%. Most stomach and bowel side effects showed up during dose increases.
Compounded semaglutide is not the same as these FDA-approved products; see compounded GLP-1. At GLP-1 SOS, semaglutide is the medicine most of our community uses, so most of the Lab is written with it in mind.
In the Lab
- GLP-1 injection day: tips and what to expect
- How long nausea lasts after a GLP-1 injection
- GLP-1 dose increase side effects: what is normal in the first week
- Is the GLP-1 pill worse for nausea or constipation than the shot?
From the people behind the Lab
You do not have to figure this out alone.
GLP-1 SOS is the daily companion made for life on a GLP-1. Plain answers like this one, a support team that replies to real questions from real people, and daily formulas like GLP-1 SOS Daily Gut Relief, designed around the side effects that come with the medication. The GLP-1 Lab is our free education arm: no login, no paywall, no hype. Side effects are part of the road. Suffering through them is not.
Sources (4)
- Wegovy (semaglutide) injection and tablets, Prescribing Information. Novo Nordisk / FDA, revised June 2026.
- Ozempic (semaglutide) injection, Prescribing Information. Novo Nordisk, revised May 2026.
- Rybelsus and Ozempic (semaglutide) tablets, Prescribing Information. Novo Nordisk / FDA, revised January 2026.
- Once-Weekly Semaglutide in Adults with Overweight or Obesity (STEP 1). New England Journal of Medicine, 2021.
Reviewed by the GLP-1 SOS editorial team · Education, not medical advice · Talk to your prescriber about your dose and your symptoms.
