Semaglutide (Ozempic, Wegovy, Wegovy Pill): What It Is, How It Works and What the Label Says

Short answer: semaglutide is a GLP-1 receptor agonist made by Novo Nordisk and sold in the US as Ozempic (a weekly injection for type 2 diabetes), Wegovy (a weekly injection, and since December 22, 2025 a daily tablet, for chronic weight management and heart risk) and Rybelsus and Ozempic tablets (daily tablets for type 2 diabetes).^[1][2][3][4] In the main Wegovy trial, body weight fell by an average of 14.9% over 68 weeks, against 2.4% on placebo.^[5] Every form carries the same boxed warning about thyroid C-cell tumors.^[2]

New to eating less? Start with what to eat when you're eating less, the guide the rest of Lighter Days builds on.

This is our reference page for semaglutide, written from the FDA prescribing information as it stands on November 13, 2026. It covers which product is approved for what and since when, how the drug works, what the headline trials found, what the label warns about, what it costs to pay directly, and where to go next on eating. Each section links to a deeper page. The other big medicine in this family has its own page: tirzepatide (Mounjaro, Zepbound).

General information, not medical advice. Nothing here tells you whether to start, stop or change a medication or a dose. That is a decision for you and your prescriber.

Semaglutide at a glance

Brand and form	FDA-approved uses (date approved)	How it's taken	Label dose range
Ozempic injection, Novo Nordisk	Blood sugar control in adults with type 2 diabetes (December 5, 2017); lowering the risk of heart attack, stroke and cardiovascular death in adults with type 2 diabetes and heart disease (January 16, 2020); lowering the risk of kidney decline, kidney failure and cardiovascular death in adults with type 2 diabetes and chronic kidney disease (January 28, 2025)[4][1]	Once a week, under the skin	Starts at 0.25 mg; maintenance 0.5, 1 or 2 mg; maximum 2 mg[1]
Wegovy injection, Novo Nordisk	Chronic weight management in adults (June 4, 2021) and in ages 12 and up (December 23, 2022); lowering the risk of heart attack, stroke and cardiovascular death in adults with heart disease and obesity or overweight (March 8, 2024); MASH, a fatty liver disease, with moderate to advanced fibrosis, under accelerated approval (August 15, 2025); a 7.2 mg dose, Wegovy HD (March 19, 2026)[4][2]	Once a week, under the skin	Starts at 0.25 mg; maintenance 1.7 or 2.4 mg; up to 7.2 mg for weight reduction in adults[2]
Wegovy tablets ("the Wegovy pill"), Novo Nordisk	Chronic weight management and lowering cardiovascular risk in adults (December 22, 2025)[4][2]	Once a day by mouth, on an empty stomach	Starts at 1.5 mg; maintenance 25 mg[2]
Rybelsus and Ozempic tablets, Novo Nordisk	Blood sugar control in adults with type 2 diabetes (Rybelsus, September 20, 2019; the newer tablet formulation now sold as Ozempic tablets, December 9, 2024); lowering cardiovascular risk in high-risk adults with type 2 diabetes (October 17, 2025)[4][3]	Once a day by mouth, on an empty stomach	Rybelsus 3 mg, then 7 or 14 mg; Ozempic tablets 1.5 mg, then 4 or 9 mg. The two are not interchangeable mg for mg[3]

Also on every semaglutide label	What it says
Boxed warning	Risk of thyroid C-cell tumors. Semaglutide caused them in rodents; whether it does in humans is unknown. Not for anyone with a personal or family history of medullary thyroid carcinoma or with MEN 2.[2][1][3]
Most common adverse reactions, Wegovy 2.4 mg injection vs placebo	Nausea 44% vs 16%, diarrhea 30% vs 16%, vomiting 24% vs 6%, constipation 24% vs 11%, abdominal pain 20% vs 10%, headache 14% vs 10%, fatigue 11% vs 5%[2]
Most common, Ozempic 1 mg vs placebo (type 2 diabetes)	Nausea 20.3% vs 6.1%, vomiting 9.2% vs 2.3%, diarrhea 8.8% vs 1.9%, abdominal pain 5.7% vs 4.6%[1]
Most common, semaglutide tablets 14 mg vs placebo (type 2 diabetes)	Nausea 20% vs 6%, abdominal pain 11% vs 4%, diarrhea 10% vs 4%, decreased appetite 9% vs 1%, vomiting 8% vs 3%[3]

The adverse reaction figures come from different trials in different people, so they are not a ranking of the products. The labels say the same thing: rates from one drug's trials cannot be compared directly with another's.^[2]

What is semaglutide?

Semaglutide is a long-acting copy of GLP-1 (glucagon-like peptide-1), a hormone the gut releases after eating. The label describes it as a GLP-1 analogue with 94% sequence homology to human GLP-1, which binds and activates the same receptor.^[2] One molecule, several brands: Ozempic and Wegovy injections contain the same active ingredient at different doses and for different approved uses, and the tablets are the same molecule made to survive the stomach.^[1][2][3] That is also why the Wegovy label says not to use it with any other semaglutide product or any other GLP-1 receptor agonist.^[2]

Two naming points cause confusion. "Ozempic" now covers both an injection and a tablet: the newer tablet formulation (1.5, 4 and 9 mg) is labeled as Ozempic tablets, alongside Rybelsus (3, 7 and 14 mg), and the shared label says the two cannot be swapped milligram for milligram.^[3] And the "Wegovy pill" is a different product from Rybelsus: a 25 mg daily tablet approved for weight management, not for diabetes.^[2]

How does semaglutide work?

The labels describe four effects:

• Appetite. GLP-1 is a natural regulator of appetite and calorie intake, and GLP-1 receptors sit in brain areas involved in appetite. In animal studies semaglutide reached and activated neurons in regions that regulate food intake. The label says it lowers calorie intake, likely by affecting appetite.^[2]
• Blood sugar. It increases insulin release and lowers glucagon, in a glucose-dependent way, meaning more when blood sugar is high. The label adds that the risk of low blood sugar rises when it is combined with insulin or a sulfonylurea.^[2]
• Slower stomach emptying. Semaglutide delays gastric emptying.^[2] This is behind much of the fullness people feel, and behind the anesthesia warning below.
• Body composition. The label says semaglutide lowers body weight with more fat mass lost than lean mass.^[2] Lean mass still falls, which is why protein and strength training matter (see the eating section).

How it lowers cardiovascular risk has not been established, the Wegovy label says.^[2] Tirzepatide works on the same receptor plus a second one, GIP; that difference is covered on our tirzepatide page.

What did the semaglutide trials find?

All of the figures below are from the FDA label or the trial's published paper. Body weight results are average percent change from the starting weight, counting everyone randomized.

Trial	Who took part	Length and dose	Main result
STEP 1 (Wegovy injection)	1,961 adults with obesity, or overweight plus a related condition; no diabetes	68 weeks; 2.4 mg weekly	Body weight −14.9% vs −2.4% on placebo[5][2]
STEP 2 (Wegovy injection)	807 adults with type 2 diabetes and a BMI of 27 or more	68 weeks; 2.4 mg	Body weight −9.6% vs −3.4%[2]
SELECT (Wegovy injection)	17,604 adults aged 45 or older with heart disease and a BMI of 27 or more, without diabetes	Median follow-up 41.8 months; 2.4 mg	Heart attack, stroke or cardiovascular death in 6.5% vs 8.0% on placebo, a 20% lower risk (hazard ratio 0.80)[6][2]
OASIS 4 (Wegovy tablet)	307 adults with obesity, or overweight plus a related condition; no diabetes	64 weeks; 25 mg daily	Body weight −13.6% vs −2.4% (label figures)[7][2]
STEP UP (Wegovy 7.2 mg)	1,407 adults with obesity, no diabetes	72 weeks; 7.2 mg or 2.4 mg	Body weight −18.8% on 7.2 mg and −15.5% on 2.4 mg, vs −3.9% on placebo[2]
ESSENCE (Wegovy injection, MASH)	800 adults with MASH and stage F2 or F3 liver fibrosis	72-week analysis; 2.4 mg	Steatohepatitis resolved without fibrosis worsening in 63% vs 34%; fibrosis improved in 37% vs 22%[8][2]
SUSTAIN 6 (Ozempic)	3,297 adults with type 2 diabetes and high cardiovascular risk	At least 2 years; 0.5 or 1 mg	Heart attack, stroke or cardiovascular death in 6.6% vs 8.9% (hazard ratio 0.74)[1]
FLOW (Ozempic)	3,533 adults with type 2 diabetes and chronic kidney disease	Median 41 months; 1 mg	Major kidney events or cardiovascular death in 18.7% vs 23.2% (hazard ratio 0.76)[1]
SOUL (semaglutide tablets)	9,650 adults with type 2 diabetes and heart or kidney disease	Median about 4 years; 14 mg daily	Heart attack, stroke or cardiovascular death in 12.0% vs 13.8% (hazard ratio 0.86)[3]

A few things to read into these numbers, and a few not to. People with type 2 diabetes saw smaller changes in body weight than people without it, in STEP 2 as in the 7.2 mg diabetes trial (−13.2% vs −3.8%).^[2] The tablet and injection figures come from different trials, so they are not a head-to-head comparison. And in SELECT, 16% stopped semaglutide because of an adverse event, against 8% on placebo.^[2] Trials also coach diet and activity: in STEP 1 everyone was counseled on a deficit of about 500 calories a day and 150 minutes of activity a week.^[2]

Semaglutide dosing: what the FDA label says

The labels raise the dose in steps to reduce digestive reactions, and allow the prescriber to delay a step if a dose is not tolerated.^[2] The two Wegovy schedules are reproduced here so you can see what the label says, not so you can follow them yourself.

What the FDA label says — not dosing advice; your prescriber sets your dose. Wegovy injection, once weekly.^[2]

Weeks	Weekly dose
1 to 4	0.25 mg (starting dose)
5 to 8	0.5 mg
9 to 12	1 mg
13 to 16	1.7 mg
17 onward	Maintenance: 2.4 mg (recommended) or 1.7 mg. For weight reduction in adults who have tolerated 2.4 mg for at least 4 weeks, the label allows up to 7.2 mg.

What the FDA label says — not dosing advice; your prescriber sets your dose. Wegovy tablets, once daily.^[2]

Days	Daily dose
1 to 30	1.5 mg (starting dose)
31 to 60	4 mg
61 to 90	9 mg
91 onward	25 mg (maintenance)

Ozempic injection starts at 0.25 mg weekly for 4 weeks, then 0.5 mg, with 1 mg and 2 mg available if more glucose control is needed.^[1] All the tablets share one rule on the label: take the tablet on an empty stomach in the morning with up to 4 ounces of plain water, and wait at least 30 minutes before food, drinks or other oral medicines.^[2][3] What that means for your morning coffee is in coffee on a GLP-1.

What does the semaglutide label warn about?

Beyond the boxed warning, the Wegovy label lists these warnings and precautions. The Ozempic and tablet labels list the same core set.^[2][1][3]

• Thyroid C-cell tumors. Seen in mice and rats; human relevance not determined. Symptoms to report include a lump in the neck, trouble swallowing, shortness of breath and persistent hoarseness.^[2]
• Acute pancreatitis, including fatal cases, has been seen with GLP-1 medications. Persistent severe abdominal pain, sometimes into the back, is the sign to act on.^[2]
• Gallbladder disease. Gallstones were reported in 1.6% on the Wegovy injection vs 0.7% on placebo, and in 2.5% on the tablet vs 1%.^[2]
• Low blood sugar, mainly with insulin or a sulfonylurea; the label suggests the prescriber consider lowering those doses.^[2]
• Acute kidney injury from dehydration. Most reported cases followed vomiting, diarrhea or nausea that led to fluid loss.^[2] Our guide to dehydration on a GLP-1 covers the signs.
• Severe digestive reactions, reported in 4.1% on the Wegovy injection vs 0.9% on placebo. Not recommended with severe gastroparesis.^[2]
• Serious allergic reactions, including anaphylaxis and angioedema.^[2]
• Diabetic eye disease can temporarily worsen with fast improvement in blood sugar; people with a history of diabetic retinopathy should be monitored.^[2]
• Heart rate. Resting heart rate rose by 1 to 4 beats a minute on average in the Wegovy trials.^[2]
• Breathing in stomach contents under anesthesia. Because the stomach empties slowly, rare cases of pulmonary aspiration have been reported during surgery or deep sedation. Tell the surgical team you take it.^[2]

Hair loss is listed too, in 3% on the 2.4 mg injection vs 1% on placebo and 6% on 7.2 mg,^[2] which our page on hair loss on Ozempic puts in context. Fatigue is covered in does Wegovy make you tired.

How much does semaglutide cost?

Prices change often. These are Novo Nordisk's own self-pay prices as of November 13, 2026, for people paying without insurance; a full cost comparison is coming as its own page.

• Wegovy injection: $349 a month for any dose from 0.25 mg to 2.4 mg, with new patients paying $199 a month for their first two fills of 0.25 or 0.5 mg through December 31, 2026. Wegovy HD (7.2 mg) is $399 a month.^[9]
• Wegovy pill: $149 a month for 1.5 mg, $199 for 4 mg, and $299 for 9 mg or 25 mg.^[9]
• Ozempic: the pen is $349 a month for 0.25 to 1 mg and $499 for 2 mg (new patients $199 for two fills), and Ozempic tablets are $149, $199 and $299 by strength. People with commercial insurance that covers it may pay as little as $25 with Novo's savings card, up to $100 a month in savings.^[10]
• List price: Novo Nordisk announced on February 24, 2026 that it will cut the list price of Wegovy, Ozempic and Rybelsus to $675 a month from January 1, 2027, about 50% off Wegovy and 35% off Ozempic. It said the change does not affect self-pay prices.^[11]

Self-pay spending does not count toward an insurance deductible, Novo's terms say.^[9] Compounded semaglutide, sold cheaper by some clinics, is a different thing from an FDA-approved product; what that means is set out in compounded GLP-1s explained.

What should you eat on semaglutide?

The labels pair semaglutide with a reduced-calorie diet and more activity, but they name no diet.^[2] The 2025 joint advisory from four US medical and nutrition societies fills that gap: protein first at every meal, small nutrient-dense meals, fiber from food, deliberate fluids, and attention to nutrients that run short when intake falls.^[12] Our pages go one question at a time:

• What to eat on Wegovy or Ozempic: a sample small-appetite day, with amounts.
• Foods to avoid on a GLP-1: what tends to sit badly with a slower stomach.
• How much protein on a GLP-1 and keeping muscle on a GLP-1, the two answers to lean mass.
• What to eat on queasy days and how much water to drink.
• Coffee and alcohol on a GLP-1.
• The whole map in one place: our GLP-1 nutrition guide.

What comes after semaglutide?

Newer medicines act on more than one receptor. Tirzepatide adds GIP, and is covered on our tirzepatide page. Retatrutide, nicknamed "GLP-3", adds glucagon as well and is still investigational: see GLP-3 (retatrutide).

For transparency about why this page is on our site: we make one product, Zornava Replenish, a lemon-lime daily hydration and nutrient powder for lighter appetite days, including for people on GLP-1 medications. It is a dietary supplement, not a medication, and it is not a substitute for anything a prescriber recommends. It is not on sale yet; early access opens February 9, 2027, and the early-access list is open now.