You may have heard about the class of Type 2 diabetes medications called glucagon-like peptide-1 (GLP-1) receptor agonists being used for weight management treatment in people who may or may not have diabetes. Medications in this class include semaglutide (brand names Ozempic®, Wegovy® and Rybelsus®), dulaglutide (brand name Trulicity®), liraglutide (brand name Saxenda®) and others.

Veronica R. Johnson, MD, a physician who specializes in obesity medicine at Northwestern Medicine, answers common questions about these medications and weight loss.

What Is GLP-1?

GLP-1 is a natural hormone in your body. It helps maintain your blood sugar levels by regulating glucose metabolism and the release of insulin (the hormone that regulates glucose).

Pharmaceutical companies have developed synthetic GLP-1 medications that mimic the hormone’s actions. These medications, often given through injections, are known as GLP-1 receptor agonists. Because they mimic the effects of GLP-1, the synthetic versions do similar things, such as:

In June 2021, the U.S. Food & Drug Administration (FDA) approved semaglutide under the brand name Wegovy for weight loss for adults; in December 2022, the same medication was approved for teens. The FDA has ruled this self-injection medication may be prescribed if you have either of the following conditions:

• A body mass index (BMI) of 27 kg/m2 or greater and have at least one weight-related condition, such as high blood pressure, Type 2 diabetes or high cholesterol
• A BMI of 30 kg/m2 or greater

In addition to weight loss, a 2023 study* has linked semaglutide to a reduction in obesity-related heart failure. The study was co-authored by Sanjiv J. Shah, MD, a cardiologist at Northwestern Medicine, and is featured in Northwestern University Feinberg School of Medicine news.

Dr. Shah says in the Feinberg School of Medicine article, “I’m really hoping that clinical trials like the ones we are doing either increase recognition of obesity-induced heart failure, leading to more frequent diagnosis, or that treatment of obesity with GLP-1 receptor agonists and other anti-obesity drugs will treat or even prevent the development of heart failure, even if it is never officially diagnosed in these patients.”

What Happens When You Stop Taking the Medication for Weight Loss?

There’s a good chance that you will regain weight. According to one study, participants who stopped taking semaglutide regained two-thirds of the weight they had lost.

“The medication not only makes you feel fuller and controls your hunger and appetite, but it also changes how your body regulates fat,” explains Dr. Johnson. “If we take that signal away, naturally your body will default back to what it was doing before.”

What About Off Brands?

Currently, there are no FDA-approved generic versions of GLP-1 medications for weight loss. With the high demand of the FDA-approved medications, as well as the high cost if your insurance won’t cover them, compounded medications have entered the marketplace.

Compounding is a method of combining or altering the ingredients of one or more medications to create another medication. Compounded medications are not FDA-approved, which means that the FDA does not verify their safety, effectiveness or quality.

Dr. Johnson strongly advises against using unregulated compounded medications for weight loss and instead recommends talking with your physician about weight-loss options.

While taking a GLP-1 medication, she adds that it is important that you are under a physician’s care to:

• Ensure dosing is accurate throughout your treatment
• Monitor your progress and any side effects
• Provide guidance on lifestyle modifications, including exercise and diet

Who Should Not Consider GLP-1 Medications?

GLP-1 medications should not be used if you:

• Are pregnant or breastfeeding
• Have a personal or family history of medullary thyroid cancer or multiple endocrine neoplasia 2A or 2B

GLP-1 medications should be used with caution if you have gastroparesis or pancreatitis. If you are considering weight-loss treatment, talk to your physician first about the approach that is right for you.

Is There Concern About Long-Term Use?

While GLP-1 medications have shown promise for weight loss, questions about long-term safety are natural.

“Because this class of medication has been studied for almost 20 years, there is significant data around its long-term use,” says Dr. Johnson. “There are no specific health concerns around using these medications for chronic disease management. However, it is important to continue to have a conversation with your prescribing physician to discuss any of your specific concerns.”

What About Lifestyle Changes?

What can often get missed are the lifestyle changes that need to accompany this type of medication for it to work at its best.

“When I see patients, I always reinforce that the medication is just a tool. It’s not a magic wand,” says Dr. Johnson. “All the things that you were doing in the past to manage your weight, like dietary changes, physical activity and good sleep are still important when you're on the medication.”

It is important to note that semaglutide is prescribed for chronic weight management and approved for long-term use. “This is not for someone who is looking to take it for a month to fit into a piece of clothing,” says Dr. Johnson.

The Bottom Line

Obesity is a chronic disease that requires long-term management, similar to heart disease and diabetes. It is also common, affecting nearly 42% of all adults in the United States and nearly 20% of children. According to the Centers for Disease Control and Prevention, obesity accounts for approximately $147 billion in annual U.S. healthcare costs.

“Weight management is preventative health care. We know that by addressing excess weight, we can improve things like blood pressure, inflammation, cholesterol levels and diabetes,” says Dr. Johnson. “We also understand this has been challenging for some people who depend on these medications to control their diabetes, and anticipate that manufacturers will be able to increase supply to meet the growing demand. These medications are helping patients live healthier lives.”

* This study was supported by Novo Nordisk, manufacturer of Ozempic and Wegovy