Head-to-head comparisons of medication uses, side effects, warnings, and more.
Key takeaways
Orlistat (Alli, Xenical) and semaglutide (Ozempic) are both used to help with weight management, but they belong to different medication classes and different primary uses. Orlistat is a lipase inhibitor that helps with weight loss by blocking the absorption of fats from your diet. It is available both over-the-counter (as Alli) and by prescription (as Xenical). Semaglutide, on the other hand, is a glucagon-like peptide-1 (GLP-1) agonist primarily used to treat Type 2 diabetes and reduce the risk of heart problems in people with diabetes. Another form of semaglutide, Wegovy, is approved for weight management, similar to orlistat. Semaglutide is administered as a weekly injection. While orlistat is taken three times a day with meals, semaglutide is injected once a week. Orlistat can cause side effects like oily stools and gas, while semaglutide may cause nausea, vomiting, and diarrhea. Orlistat can interact with medications like levothyroxine (Synthroid, Levoxyl, Tirosint) and warfarin (Coumadin, Jantoven), whereas semaglutide can cause low blood sugar if taken with other diabetes medications. Orlistat is not recommended for those with chronic malabsorption syndrome, while semaglutide should be avoided if you have a history of certain thyroid cancers.
Orlistat
Ozempic (semaglutide)
Orlistat
Ozempic (semaglutide)
Summary of Orlistat vs. Ozempic
Summary for Lipase inhibitor
Orlistat is a medication that works alongside diet and exercise to increase weight loss in people who are overweight or obese. It needs to be taken three times a day and is available with a prescription in a higher dose (Xenical) or over the counter in a lower dose (Alli).
Summary for GLP-1 agonist
Prescription only
Ozempic (semaglutide) is a prescription injection used with diet and exercise to help manage Type 2 diabetes in adults. It's also FDA approved to lower the risk of heart attack, stroke, and heart-related death in those with Type 2 diabetes and heart disease. In addition, it can reduce the risk of worsening kidney problems in people with Type 2 diabetes and chronic kidney disease (CKD). Ozempic (semaglutide) is a GLP-1 agonist that's injected under the skin once a week. Common side effects include nausea, vomiting, and diarrhea.
Indications of Orlistat vs. Ozempic
Indications for
Xenical (orlistat):
•Obesty management in adults with a body mass index (BMI) of:
•30 kg/m^2^ or greater or
•27 kg/m^2^ or greater and at least one weight-related condition (e.g., high blood pressure, type 2 diabetes, or high cholesterol)