What Is Zepbound?
Zepbound is the brand name of tirzepatide, a once-weekly prescription injection the FDA approved in November 2023 for chronic weight management in adults, alongside a reduced-calorie diet and more physical activity. In December 2024, the FDA also approved it for moderate to severe obstructive sleep apnea (OSA) in adults with obesity.
Zepbound mimics two gut hormones to reduce appetite and food intake. The same active ingredient is sold as Mounjaro, which is approved to improve blood sugar in adults with type 2 diabetes.
Zepbound at a Glance
| Generic name | Tirzepatide |
|---|---|
| What it treats | Obesity, or overweight with at least one weight-related condition, in adults. Moderate to severe OSA in adults with obesity. |
| Drug class | GIP and GLP-1 receptor agonist |
| How it's given | Weekly injection under the skin, by pen, vial or KwikPen |
| How long it lasts | Half-life of about 5 days. Meant for long-term use. |
| Common side effects | Nausea, diarrhea, vomiting and constipation |
| Boxed warning | Thyroid C-cell tumors in rats; human risk unknown |
| FDA status | Approved for adults in 2023 (weight) and 2024 (OSA). Not established in children. |
Who Is Zepbound For?
Zepbound is for adults with a body mass index (BMI) of 30 or higher, or a BMI of 27 or higher plus at least one weight-related condition such as high blood pressure, type 2 diabetes or high cholesterol. It adds to diet and exercise, not replacing them.
The Obesity Medicine Association lists four pillars of obesity treatment: nutrition therapy, physical activity, behavior change and medical interventions such as medication. The American Diabetes Association's 2026 Standards of Care call obesity a chronic, often relapsing disease. They note that in people with type 2 diabetes, losing 5% to 7% of body weight improves blood sugar, blood pressure and blood fats.
How Does Zepbound Work?
Zepbound works by activating receptors for two hormones made in the intestine, GIP (glucose-dependent insulinotropic polypeptide) and GLP-1 (glucagon-like peptide-1). Both receptors are found in areas of the brain involved in appetite. GLP-1 is a natural regulator of appetite and calorie intake, and nonclinical studies suggest GIP may add to this effect. Zepbound also slows stomach emptying and helps the pancreas release insulin when blood sugar is high.
How Is Zepbound Taken?
Zepbound is injected under the skin of the abdomen or thigh once a week, at any time of day, with or without meals. Another person can give the shot in the back of the upper arm. Rotate the site with each dose.
- Starting dose: 2.5 mg weekly for 4 weeks, then 2.5 mg increases at least 4 weeks apart to limit digestive side effects.
- Maintenance: 5 mg, 10 mg or 15 mg weekly (10 mg or 15 mg for OSA). The maximum is 15 mg a week.
- Missed dose: take it within 4 days; after that, skip it. Keep doses at least 3 days apart.
How Much Weight Do People Lose on Zepbound?
In a 72-week trial, adults without diabetes lost an average of about 15% to 21% of their body weight on Zepbound, depending on the dose. Everyone in the trial also got diet and activity counseling.
- In that trial of 2,539 adults, average change was −15.0% on 5 mg, −19.5% on 10 mg and −20.9% on 15 mg, compared with −3.1% on placebo.
- 56.7% of people on 15 mg lost at least 20% of their body weight, compared with 3.1% on placebo.
- In a second 72-week trial, people with type 2 diabetes averaged −12.8% on 10 mg and −14.7% on 15 mg, versus −3.2% on placebo.
- In the SURMOUNT-4 trial, people lost an average of 20.9% over 36 weeks. Those switched to placebo then regained 14.0% over 52 weeks, while those who stayed on Zepbound lost another 5.5%.
What Are the Side Effects of Zepbound?
The most common side effects of Zepbound affect digestion, and most nausea, vomiting and diarrhea happens during dose increases.
Common side effects
In the two main weight trials, nausea affected 25% to 29% of people on Zepbound (8% on placebo), diarrhea 19% to 23%, constipation 11% to 17% and vomiting 8% to 13%. Stomach pain, indigestion, injection-site reactions, fatigue, hair loss and acid reflux also happened more often than with placebo.
Serious risks
- Thyroid C-cell tumors (boxed warning). Report a neck lump, hoarseness, trouble swallowing or shortness of breath.
- Pancreatitis: stomach pain that won't go away and may spread to the back
- Severe digestive reactions, gallbladder disease and kidney injury from fluid loss
- Serious allergic reactions, including anaphylaxis and angioedema
- Low blood sugar when used with insulin or a medicine that makes the body release insulin, such as a sulfonylurea
- Inhaling stomach contents during general anesthesia or deep sedation. Tell your care team about Zepbound before any planned procedure.
Who shouldn't take Zepbound
- People with a personal or family history of medullary thyroid carcinoma, or with MEN 2 (multiple endocrine neoplasia syndrome type 2)
- People with a serious allergy to tirzepatide
- People who are pregnant. Stop Zepbound when pregnancy is recognized.
- People with severe gastroparesis, or who take Mounjaro or another GLP-1 receptor agonist
If you use birth control pills, switch to a non-oral method or add a barrier method for 4 weeks after starting Zepbound and after each dose increase.
Zepbound vs. Mounjaro, Wegovy and Compounded Tirzepatide
Zepbound shares its active ingredient with Mounjaro, while Wegovy acts on one hormone receptor instead of two.
| Active ingredient | FDA-approved use | FDA-approved? | |
|---|---|---|---|
| Zepbound | Tirzepatide (GIP and GLP-1) | Weight management and OSA in adults | Yes |
| Mounjaro | Tirzepatide | Blood sugar control in adults with type 2 diabetes | Yes |
| Wegovy | Semaglutide (GLP-1 only) | Weight management in adults and children 12 and older | Yes |
| Compounded tirzepatide | Tirzepatide made by a compounding pharmacy | None | No. The FDA doesn't review it for safety, effectiveness or quality. |
Zepbound at GENEVA
At GENEVA Primary Care & Med Spa in Alpharetta, GA, a provider evaluates your weight concerns, health history and current medicines. Based on that evaluation, your provider recommends treatment at GENEVA or a referral to a specialist.
You can start with a medical weight loss consultation or a primary care visit. GENEVA serves patients from Alpharetta, Johns Creek, Milton, Roswell and Cumming.
Related Terms
- Tirzepatide Injections
- Mounjaro
- Wegovy
- Dual GIP/GLP-1 Agonist
- Tirzepatide Titration Schedule
- Compounded Tirzepatide
- Sleep Apnea
Zepbound FAQs
Is Zepbound the same as Mounjaro?
Zepbound and Mounjaro contain the same active ingredient, tirzepatide, but they are approved for different uses. Mounjaro is approved, with diet and exercise, to improve blood sugar in adults with type 2 diabetes. Zepbound is approved for chronic weight management in adults with obesity, or overweight plus a weight-related condition, and for moderate to severe sleep apnea in adults with obesity. The Zepbound label says not to combine it with Mounjaro or any GLP-1 receptor agonist.
How much weight can you lose on Zepbound?
In a 72-week clinical trial, adults without diabetes lost an average of about 15% to 21% of their body weight on Zepbound, depending on the dose. The average change was −15.0% on 5 mg, −19.5% on 10 mg and −20.9% on 15 mg, compared with −3.1% on placebo. NIDDK advises that if you haven't lost at least 5% of your starting weight after 12 weeks on the full dose, your clinician will probably recommend stopping.
What are the most common side effects of Zepbound?
The most common side effects of Zepbound are nausea, diarrhea, vomiting and constipation, and most nausea, vomiting and diarrhea happens while the dose is being increased. In the main weight trials, nausea affected 25% to 29% of people on Zepbound, compared with 8% on placebo. Stomach pain, indigestion, injection-site reactions, fatigue and hair loss also happened more often than with placebo. Call your clinician right away for stomach pain that won't go away and may spread to your back, a possible sign of pancreatitis.
What happens when you stop taking Zepbound?
You will probably regain some weight after stopping Zepbound. NIDDK calls obesity a chronic disease and says that if you have lost enough weight to improve your health and have no serious side effects, your clinician may advise staying on the medicine indefinitely. In the SURMOUNT-4 trial, adults lost an average of 20.9% of their weight over 36 weeks. Those switched to placebo regained 14.0% over the next 52 weeks, while those who stayed on Zepbound lost another 5.5%. NIDDK notes that keeping up healthy eating and physical activity may help you regain less. Talk with your clinician before stopping.
Is Zepbound better than Wegovy for weight loss?
In a head-to-head trial, tirzepatide, the active ingredient in Zepbound, led to more weight loss than semaglutide, the active ingredient in Wegovy. In SURMOUNT-5, 751 adults with obesity but without type 2 diabetes lost an average of 20.2% of their weight on tirzepatide and 13.7% on semaglutide after 72 weeks. Digestive side effects were most common in both groups, and most were mild to moderate. Wegovy is also approved for children 12 and older; Zepbound is for adults only.
Can a primary care provider prescribe Zepbound?
A primary care provider can evaluate whether Zepbound may fit your health needs, then treat you or refer you to a specialist. The FDA approved Zepbound for adults with a BMI of 30 or higher, or 27 or higher with at least one weight-related condition. At GENEVA in Alpharetta, a provider reviews your weight history, health conditions, family history of thyroid cancer and current medicines. The provider then recommends either treatment at GENEVA or a referral to a specialist. Under the FDA label, the dose goes up no sooner than every 4 weeks. The maintenance dose is chosen based on how well it works and how well you tolerate it.