GLP-1 Drugs: How do drugs like Ozempic, Mounjaro, and others work?

They go by brand names such as Ozempic, Wegovy, Zepbound, and Mounjaro, and they have become some of the most talked-about drugs in the world. Celebrities use them, doctors prescribe them in record numbers, and millions of people credit them with losing weight.

But what exactly are GLP-1 drugs, and how do they work?

What are GLP-1 drugs?

GLP-1 stands for Glucagon-Like Peptide-1, a hormone the body naturally produces after eating. It helps regulate blood sugar levels and tells the brain that you are full, as per Cleveland Clinic.GLP-1 medications are synthetic versions of this hormone. They were first designed to treat type 2 diabetes, helping patients manage blood sugar. During treatment, doctors noticed something unexpected: many people were losing a large amount of weight (Harvard Health).This led to the use of semaglutide (sold as Ozempic and Wegovy) and tirzepatide (sold as Mounjaro and Zepbound) for weight management as well as diabetes.

How do they work?

GLP-1 drugs activate the same receptors in the brain and gut that respond to natural GLP-1, leading to appetite suppression and slower digestion, as per a research published in StatPearls in 2024.Scientists note that the hormone influences both central and peripheral pathways to reduce hunger and promote satiety as per a 2025 study published in the American Journal of Medicine, titled Mechanisms of GLP-1RA-Induced Weight Loss.

Together, these effects make it easier to eat less and lose weight. Many people lose around 10 to 15 percent of their body weight over time, according to a 2021 study published in the New England Journal of Medicine.

Are they safe?

Common side effects include nausea, constipation, and tiredness. Doctors usually start patients on a low dose to reduce these problems. Long-term studies show benefits beyond weight loss, such as a lower risk of heart attacks and strokes(PubMed). However, weight often returns if the medication is stopped.

The bottom line

GLP-1 drugs copy a natural hormone that helps control hunger and blood sugar. They have changed how obesity is treated, offering new hope for millions. But they work best when combined with healthy food, regular exercise, and medical supervision.Note: The information provided in this article is for educational purposes only and is not intended as medical advice. Always consult with a healthcare professional before starting any new medication or treatment.