In the US, four GLP-1-pathway medicines are labeled for weight management: Wegovy (semaglutide, as a weekly injection or a daily tablet), Zepbound (tirzepatide, weekly injection), Saxenda (liraglutide, daily injection) and Foundayo (orforglipron, daily tablet). Ozempic, Mounjaro, Victoza and Rybelsus are labeled for type 2 diabetes instead. All of them are prescription drugs started at a low dose and increased in steps. This guide covers how they differ, how the dosing works, and what to keep track of. Your prescriber chooses the drug and dose.
What these medicines do
GLP-1 is a gut hormone involved in regulating appetite and food intake. The Wegovy label says GLP-1 receptors are present in brain regions involved in appetite regulation, and that the drug delays gastric emptying (Wegovy prescribing information, sections 12.1 and 7.2). Tirzepatide acts on both the GLP-1 and GIP receptors (Zepbound prescribing information, section 12.1).
The WHO, in its first guideline on these drugs, describes obesity as a chronic, relapsing disease and conditionally recommends GLP-1 therapies for long-term use in adults, together with healthy diet, physical activity and professional support (WHO). For the biology and trial results in more depth, see how GLP-1 medications support weight loss.
The four weight-management medicines at a glance
| Wegovy | Zepbound | Saxenda | Foundayo | |
|---|---|---|---|---|
| Active ingredient | semaglutide | tirzepatide | liraglutide | orforglipron |
| Approved for | Weight reduction and maintenance in adults with obesity, or overweight with a weight-related condition (also ages 12+ with obesity); lower cardiovascular risk in certain adults; MASH with liver fibrosis | Weight reduction and maintenance in adults with obesity, or overweight with a weight-related condition; moderate to severe obstructive sleep apnea in adults with obesity | Weight reduction and maintenance in adults with obesity or overweight with a weight-related condition; ages 12+ with obesity and body weight above 60 kg | Weight reduction and maintenance in adults with obesity, or overweight with a weight-related condition |
| Schedule | Once weekly injection; or once daily tablet | Once weekly | Once daily | Once daily tablet, with or without food |
| Starting dose | 0.25 mg weekly (injection); 1.5 mg daily (tablet) | 2.5 mg weekly for 4 weeks | 0.6 mg daily for one week | 0.8 mg daily for at least 30 days |
| Maker | Novo Nordisk | Eli Lilly | Novo Nordisk | Eli Lilly |
Sources: Wegovy label, sections 1 and 2; Zepbound label, sections 1 and 2; Saxenda label, sections 1 and 2; Foundayo label, sections 1 and 2.
If you’re comparing the semaglutide brands, read Ozempic vs Wegovy; for tirzepatide against semaglutide, Zepbound vs Wegovy.
How the dose steps work
The starting dose is not meant to be the long-term dose. Labels use stepwise increases to reduce the risk of digestive side effects.
Wegovy injection (once weekly): 0.25 mg for weeks 1 to 4, 0.5 mg for weeks 5 to 8, 1 mg for weeks 9 to 12, 1.7 mg for weeks 13 to 16, then a maintenance dose from week 17: 1.7 mg or 2.4 mg (2.4 mg recommended for weight reduction). If a dose isn’t tolerated, the label says to consider delaying escalation for 4 weeks (Wegovy label, section 2.2). The label also describes a higher 7.2 mg dose for adults who tolerate 2.4 mg for at least 4 weeks and need more weight loss.
Wegovy tablet (once daily): 1.5 mg for days 1 to 30, 4 mg for days 31 to 60, 9 mg for days 61 to 90, then 25 mg from day 91 (Wegovy label, section 2.3). It’s taken on an empty stomach with water, with a 30-minute wait before eating.
Zepbound: 2.5 mg weekly for 4 weeks, then 5 mg; further increases are in 2.5 mg steps after at least 4 weeks on the current dose. Maintenance doses for weight reduction are 5, 10 or 15 mg, and 15 mg is the maximum (Zepbound label, sections 2.1 and 2.2). See our Zepbound dosage schedule guide.
Saxenda: 0.6 mg daily in week 1, 1.2 mg in week 2, 1.8 mg in week 3, 2.4 mg in week 4, then 3 mg daily from week 5 (Saxenda label, Table 1).
Foundayo (once daily tablet): 0.8 mg, then 2.5 mg after at least 30 days, then 5.5 mg after at least 30 more days. Based on response and tolerability, the dose can go up to 9 mg, 14.5 mg or 17.2 mg, with at least 30 days on each step; 17.2 mg is the maximum (Foundayo label, section 2.1). It can be taken with or without food.
Missed doses have their own rules. For example, Wegovy injection should be taken as soon as possible if the next dose is more than 2 days away, and if two or more doses in a row are missed, the label says to restart escalation at a lower dose. Zepbound allows a missed dose within 4 days. Follow your own label and ask your prescriber or pharmacist.
What to expect
Trial averages on the labels: in adults with obesity or overweight and a weight-related condition, Wegovy 2.4 mg produced an average -14.9% weight change at 68 weeks against -2.4% on placebo; Zepbound produced -15.0%, -19.5% and -20.9% at 5, 10 and 15 mg at 72 weeks against -3.1%; Saxenda -7.4% at 56 weeks against -3.0%; Foundayo -7.4%, -8.3% and -11.1% at 5.5, 9 and 17.2 mg at 72 weeks against -2.1% in adults without diabetes (Wegovy, Zepbound, Saxenda and Foundayo labels). These are averages from separate trials, with people also receiving diet and activity advice. Individual results differ.
Stopping has an effect too. In the STEP 1 extension, people who stopped semaglutide 2.4 mg regained about two-thirds of the weight they had lost within a year (Diabetes, Obesity and Metabolism). Plan long-term use with your prescriber.
Side effects
The most common are nausea, diarrhea, vomiting, constipation and abdominal pain. In the Wegovy trials, 44% of people on 2.4 mg reported nausea (16% on placebo) (Wegovy label, Table 3). The labels warn about pancreatitis, gallbladder disease, kidney injury from dehydration and serious allergic reactions, and carry a boxed warning for thyroid C-cell tumors. Report severe or persistent symptoms to your prescriber. Our guide to GLP-1 side effects has the details.
What to track
A short, consistent log is more useful than a detailed one you drop after a week.
- Injection day, dose and site, so you can match symptoms to dose steps.
- Side effects, with severity and how long after the shot they appeared.
- Food and protein. Cleveland Clinic advises prioritizing protein and working with a dietitian on the amount, because lower hunger can make it hard to eat enough (Cleveland Clinic).
- Fluids. Dehydration from digestive side effects is a labeled risk.
- Weight, measured the same way each week, and how you feel.
Mingo is a GLP-1 tracker for iPhone and Android where you can log shots and doses, food and protein, side effects and weight in one place. It doesn’t replace your doctor or give medical advice. Get the app, or read our guide to tracking GLP-1 weight loss.
Working with your care team
The labels describe the weight-management drugs as used with a reduced-calorie diet and increased physical activity, and the WHO guideline says behavioral support may be offered with them. Bring your log to appointments, tell your prescriber about every other medicine you take, and ask before changing any dose. Also ask how long you’re expected to stay on treatment, and what happens if you stop.
Key takeaways
- Wegovy, Zepbound, Saxenda and Foundayo are the US-labeled GLP-1-pathway medicines for weight management; Ozempic, Mounjaro, Victoza and Rybelsus are labeled for type 2 diabetes.
- Every one starts at a low dose and steps up; the first dose is not the treatment dose.
- Trial averages are substantial but individual results vary, and weight tends to return after stopping.
- Log doses, side effects, protein, fluids and weight, and bring the log to appointments.
Frequently asked questions
What is a GLP-1 weight loss medication?
It is a prescription medicine that activates the GLP-1 receptor (tirzepatide also activates the GIP receptor) and is labeled for weight reduction and maintenance in adults with obesity, or overweight plus a weight-related condition, alongside diet and activity changes. Wegovy, Zepbound, Saxenda and Foundayo are the US examples.
How do GLP-1 medications help with weight loss?
They act on receptors involved in appetite regulation and slow stomach emptying, so many people feel full sooner and eat less. In trials, people on them lost more weight than people on placebo.
Are GLP-1 medications safe for everyone?
No. They are contraindicated in people with a personal or family history of medullary thyroid carcinoma or MEN 2, and the labels list other warnings, including for pancreatitis, gallbladder disease and pregnancy. A prescriber needs to review your history first.
How should I track my progress on a GLP-1?
Record your injection day and dose, side effects, food with protein, fluids and weight, and review the trend weekly rather than daily. Bring the log to your appointments.
What are common side effects of GLP-1 medications?
Nausea, diarrhea, vomiting and constipation are the most common, especially while the dose is rising. Contact your prescriber about severe or lasting symptoms, severe stomach pain, or signs of an allergic reaction.
