GLP-1 Medications (Ozempic, Wegovy, Mounjaro): What to Know Before You Start

How they work

GLP-1 is a natural gut hormone released after eating. Medicines such as semaglutide (Ozempic, Wegovy) and tirzepatide (Mounjaro, Zepbound, which also acts on GIP) mimic it. They help the pancreas release insulin when blood sugar is high, slow how fast the stomach empties and reduce appetite.

Who they are approved for

Depending on the brand, these drugs are FDA-approved for type 2 diabetes, for chronic weight management in adults with obesity or overweight plus a weight-related condition, and in some cases to lower cardiovascular risk. Your doctor decides which, if any, fits you.

Common side effects

Most side effects are digestive and often ease as the dose is slowly increased.

• Nausea, vomiting, diarrhea or constipation
• Feeling full quickly and reduced appetite
• Fatigue or mild headache early on
• Less common but serious: pancreatitis, gallbladder problems, severe dehydration — seek care for severe, persistent abdominal pain

Protecting muscle while losing weight

Rapid weight loss can include muscle loss. Eating enough protein at each meal and doing strength training two or more times a week helps preserve muscle and strength.

Questions to ask your doctor

• Is this medicine appropriate given my health history and other medicines?
• What dose schedule will we follow, and what side effects should prompt a call?
• Will my insurance cover it, and what happens if I stop?
• Avoid unregulated online "compounded" versions unless your clinician and a licensed pharmacy supply them.

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