Semaglutide is an injectable prescription medication used to treat both diabetes and obesity, two closely linked medical conditions. Semaglutide belongs to a class of drugs called GLP-1 (glucagon-like peptide-1) receptor agonists, which mimic the hormone our bodies naturally produce when we eat.
Ozempic and Wegovy, branded forms of semaglutide, are made by the Danish pharmaceutical company Novo Nordisk. Their active ingredients are identical, but these drugs have distinct dosing recommendations and different FDA approvals:
- Ozempic is approved by the U.S. Food and Drug Administration (FDA) for the treatment of Type 2 diabetes.
- Wegovy is FDA approved for chronic weight management for adults with obesity. In 2021, the FDA approved Wegovy to treat obesity in people with a body mass index (BMI) over 30, or a BMI of 27 with at least one weight-related medical condition such as sleep apnea, fatty liver disease, high blood pressure, or high cholesterol. In 2022, Wegovy was approved to treat obesity in adolescents over age 12 with a BMI at or above the 95th percentile for their age and sex.
- Rybelsus is an oral semaglutide tablet that is FDA approved to treat type 2 diabetes mellitus.
Tirzepatide is frequently mentioned in relation to semaglutide, but it’s not the same drug—more like a distant cousin. According to its manufacturer, “It works differently by directly activating GIP and GLP-1 pathways to help regulate blood sugar.”
There are currently two FDA-approved branded forms of tirzepatide:
- Mounjaro is approved for Type 2 diabetes.
- Zepbound is approved to treat obesity or patients who are overweight, with at least one weight-related condition.
Related: The Differences Between Ozempic, Wegovy, Mounjaro, and Other Popular Weight-Loss Drugs
Since its initial approval, the popularity of semaglutide as a weight loss drug has exploded on social media, and a number of suddenly-skinny celebrities have been linked to the shot.
“More than a year into the semaglutide craze (and the Marilyn dress at the Met) we know it works and biology wins over willpower,” says Dr. Sharon Giese, a board-certified plastic surgeon in New York City who prescribes semaglutide as part of a holistic weight management program. “Most who have tried to lose weight know it is not easy. Even Weight Watchers is rewriting their original message of ‘choice not chance,’” Dr. Giese points out.
She points to powerful feelings of deprivation as “part of the reason for yo-yo dieting and failures.” Dr. Giese explains that semaglutide, the active ingredient of Ozempic and Wegovy, “slows stomach emptying, making you feel full faster and longer. This sends a message to the brain that you are not hungry.”
Simply put, those who take the drug eat less, so they consume fewer calories and lose weight. What’s more, “people do not experience the same sense of deprivation they do when they diet alone,” says Dr. Giese. “You will lack the desire to overeat and possibly over-indulge in alcohol because fluid is also filling.” She also notes another benefit: patients experience less “food noise,” intrusive thoughts about food.
According to Dr. Giese, “the brain helps maintain the body’s set-point by regulating how much to eat. Many propose these GLP-1 agonists lower the set-point by sending feedback to the brain that they are not hungry. In effect, people’s ‘set-point’ is reset, aiding the weight loss process.”
The weight loss can seem rapid to people who have struggled for years to shed pounds, but Dr. Giese says her patients are “losing weight and adjusting their behavior on their own, gradually. Eating less over an extended period of time results in slow, steady, real weight loss—not rapid weight loss.”
Related: Oprah Winfrey Reveals She’s Taking Ozempic


