Typical dose0.25 mg rising to 1.7–2.4 mg (max 7.2 mg)
How oftenOnce a week
Half-lifeAbout 1 week (FDA label); it stays in the blood for about 5 weeks after the last dose
Vial sizes2 mg, 5 mg, 10 mg
The simple version
What it does
It turns down hunger and slows digestion, so you eat less and lose weight.
How people take it
Wegovy starts at 0.25 mg once a week and steps up every 4 weeks to 1.7–2.4 mg.
Know this
Most people regain much of the weight when they stop, and stomach side effects are common.
What it is
Semaglutide is a lab-made copy of GLP-1, a hormone your gut releases after you eat, tweaked to last about a week instead of a few minutes. It's the active ingredient in Ozempic and Wegovy (weekly shots) and in Rybelsus and the Wegovy pill (daily tablets). It's one of the most studied weight-loss drugs ever made.
How it works
It tells your brain you're full and helps your body release insulin when blood sugar is high. It also makes food leave your stomach more slowly, so you stay full longer. You lose weight because you eat less, not because it burns fat directly.
FDA-approved for: Type 2 diabetes (2017, Ozempic); chronic weight management (2021, Wegovy); heart-risk reduction, kidney disease in diabetes and MASH liver disease
What people use it for
Weight loss
Blood sugar control in type 2 diabetes
Lowering heart attack and stroke risk
Quieting constant food thoughts and cravings
The evidence
FDA-approved
The evidence is about as solid as it gets. In the STEP 1 trial, adults without diabetes on 2.4 mg a week lost about 15% of their body weight over 68 weeks, versus about 2% on a dummy shot, and big heart trials showed fewer heart attacks, strokes and heart deaths. The catch is that most people regain much of the weight when they stop, and stomach side effects are common, especially while the dose is going up.
Same day each week, any time of day, with or without food
Cycle
Ongoing. Step up every 4 weeks (see titration), then stay on the maintenance dose
Route
Subcutaneous injection (belly, thigh or upper arm)
Why: It lasts about a week in the body, so one shot a week keeps levels steady. Going up slowly every 4 weeks gives your gut time to adjust and cuts down on nausea. The label lets some adults go above 2.4 mg, up to 7.2 mg a week.
Type 2 diabetes (Ozempic label)
Label dose
Dose
0.25 mg rising to 0.5, 1 or 2 mg
How often
Once a week
When
Same day each week, any time of day
Cycle
Ongoing. 0.25 mg is a starter dose only; go up only after at least 4 weeks on each dose
Route
Subcutaneous injection
Why: The diabetes label tops out lower because the goal is blood sugar control. Many people get there on 0.5 or 1 mg.
Wegovy tablet (label)
Label dose
Dose
1.5 mg rising to 25 mg
How often
Once a day
When
First thing in the morning on an empty stomach with a small sip of water; wait 30 minutes before eating or other pills
Cycle
Ongoing. 1.5 mg, 4 mg, 9 mg, then 25 mg, each for 30 days
Route
By mouth
Why: Very little semaglutide gets absorbed through the gut, so tablet doses are much higher than shot doses. Don't use these numbers for shots.
Low-dose maintenance
Reported
Dose
0.25–1 mg
How often
Once a week
When
Same day each week
Cycle
Ongoing, often after reaching a goal weight on a higher dose
Route
Subcutaneous injection
Why: Some people stay at the lowest dose that controls their appetite to keep side effects and cost down. This hasn't been tested for keeping weight off.
Step-up schedule
Weeks
Dose
1–4
0.25 mg once a week (Wegovy and Ozempic). Starter dose only.
5–8
0.5 mg once a week. Ozempic users may stay here.
9–12
1 mg once a week. Ozempic: go up only if more blood-sugar control is needed.
13–16
1.7 mg once a week (Wegovy). Ozempic's next and top step is 2 mg after at least 4 weeks on 1 mg.
17 on
2.4 mg once a week (Wegovy maintenance; 1.7 mg is also allowed). Some adults may go up to 7.2 mg under the label.
Start at the low end, and change one thing at a time. If you take medication or have a health condition, check with a doctor first.
We may earn a commission from these links. Counts include one syringe and two swabs per dose.
Stay safe
Side effects
Nausea, vomiting, diarrhea or constipation (very common, worst while the dose is going up)
Stomach pain, burping, bloating, heartburn
Tiredness and low appetite
Dehydration from vomiting or diarrhea, which can strain the kidneys
Gallbladder problems, including gallstones
Pancreatitis (rare): severe belly pain that spreads to your back, with or without vomiting
Low blood sugar when combined with insulin or sulfonylureas
Faster resting heart rate
Diabetes-related eye problems getting worse in people with diabetes
Losing muscle along with fat if you don't get enough protein and strength training
Skip it if
You or a family member had medullary thyroid cancer or MEN 2 (boxed warning: it caused thyroid tumors in rodents)
Pregnant, trying to get pregnant, or breastfeeding (stop at least 2 months before trying to conceive)
Past pancreatitis
Severe problems with your stomach emptying (gastroparesis)
Type 1 diabetes (it doesn't replace insulin)
Under 12, or an eating disorder
Surgery or a scope procedure (endoscopy) coming up soon: tell the doctor, because food may still be in your stomach
Interactions
Insulin or sulfonylureas (glipizide, glyburide, glimepiride): higher risk of low blood sugar; doses often need lowering
Other GLP-1 or GIP/GLP-1 drugs (tirzepatide, liraglutide, retatrutide): don't combine
Pills that need exact timing or levels (like warfarin or thyroid medicine): a slower stomach can change how they absorb
Get help right away for swelling of the face or throat, trouble breathing, chest pain, or a spreading, hot, red injection site.
Storage & legal
Storage
Pens: keep in the fridge. An Ozempic pen can stay at room temperature (up to 30 °C) for up to 56 days after first use, and Wegovy single-dose pens can sit out for up to 28 days. Powder: fridge or freezer. Once mixed: fridge, use within about 4 weeks. Never freeze a mixed vial or pen.
Legal status
FDA: FDA-approved (Ozempic, Wegovy, Rybelsus). Compounded versions are not FDA-approved.
Most people regain a good part of it within a year of stopping, because their appetite comes back. Many treat it as long-term, or taper slowly while building eating and exercise habits.
Why go up so slowly?
Nausea and vomiting get worse at higher doses, and each 4-week step gives your gut time to adjust. If a step is rough, staying at your current dose longer is a common and sensible choice.
Can I mix it with tirzepatide or retatrutide?
No. They hit the same target, so you just stack up the side effects, including dehydration and pancreatitis risk.
Is the tablet the same as the shot?
Same drug, very different numbers. Tablets need far higher doses because most of the drug isn't absorbed, so never turn tablet doses into shot doses.
Sources
Wegovy (semaglutide) injection and tablets, US prescribing information. Novo Nordisk; DailyMed, 2026. Source
Ozempic (semaglutide) injection, US prescribing information. Novo Nordisk; DailyMed, 2026. Source
Wilding JPH, et al. Once-Weekly Semaglutide in Adults with Overweight or Obesity. N Engl J Med. 2021;384(11):989-1002. PubMed 33567185
Marso SP, et al. Semaglutide and Cardiovascular Outcomes in Patients with Type 2 Diabetes. N Engl J Med. 2016;375(19):1834-1844. PubMed 27633186
Lincoff AM, et al. Semaglutide and Cardiovascular Outcomes in Obesity without Diabetes. N Engl J Med. 2023;389(24):2221-2232. PubMed 37952131