The Consumer’s Guide to GLP-1 Agonists for Type 2 Diabetes and More

Currently, there are three GLP-1 receptor agonists on the market:

• dulaglutide (Trulicity)
• liraglutide (Victoza)
• semaglutide (Ozempic and Rybelsus)

There is also a similar medication called tirzepatide (Mounjaro/Zepbound), which is a dual GLP-1/GIP receptor agonist. This means it works on GLP-1, as well as another receptor called glucose-dependent insulinotropic polypeptide, which also releases insulin.

Three brands of the available GLP-1 agonists are given by injection, either daily or weekly:

Once a day (at any time):

• liraglutide (Victoza)

Once a week:

• dulaglutide (Trulicity)
• semaglutide (Ozempic)

Another semaglutide, Rybelsus, is available in pill form and taken once a day.

The dual GLP-1/GIP receptor agonist tirzepatide (Mounjaro/Zepbound) is a once-weekly injection.

Every person is different, but “Generally, people will start to see improvements in their blood glucose in the first few days,” says Joshua J. Neumiller, PharmD, a professor and vice chair of pharmacotherapy at Washington State University in Spokane and president of healthcare and education for the American Diabetes Association (ADA).

That said, medication that is taken once a week is longer acting, so it may take several weeks to provide the full benefit, he notes.

Although not all GLP-1 agonists are approved for weight loss, they often can help you lose weight, mainly because they slow digestion and increase satiety. But they can also reduce “food noise” — the constant rumination about and preoccupation with food.

In fact, the ADA considers the effectiveness of Ozempic and Mounjaro to be “very high” for weight loss, Neumiller says.

Beyond lowering blood sugar levels and reducing weight, GLP-1 agonists can reduce the risk for heart disease and kidney disease. One review found that GLP-1 agonists promote weight loss and improve blood pressure and blood lipid levels, which has a positive impact on cardiovascular risk factors.

The meds also stimulate the endothelium (the lining of the blood vessels) to produce nitric oxide, which is crucial for healthy blood vessel function. It also lowers the levels of oxidative stress that can lead to cell and tissue damage, according to some research.

Another study found that GLP-1 agonists are associated with a lower risk of major adverse kidney events and death from cardiovascular causes in people with type 2 diabetes and chronic kidney disease.

Finally, GLP-1 agonists can also help treat or reduce the risk for heart failure, metabolic dysfunction–associated fatty liver, stroke and obstructive sleep apnea in some people, says Dr. Gutierrez. Ozempic, for example, is approved by the U.S. Food and Drug Administration (FDA) to reduce the risk of cardiovascular problems in people with type 2 diabetes and heart disease, while Zepbound is approved to treat obstructive sleep apnea.

Clinical trials are also testing the medication as a possible treatment for other conditions, including kidney failure, addiction, Alzheimer’s disease, and more, according to some research.

GLP-1 agonists can be very effective at lowering blood sugar levels, but you may still need to take additional medications to reach your goals. “It depends on the patient,” says Gutierrez. “If your diabetes is advanced, you may still need to take insulin or another medication.”

But if you are already taking insulin, you may be able to decrease your dose (or maybe stop it completely) if taking a GLP-1 agonist is effective, Neumiller says. Work with your healthcare team to figure out which meds work best for you.

To avoid nausea, your doctor may start you on a small dose of the GLP-1 agonist and then gradually increase it. If you do have nausea when you first start taking a GLP-1, know that it’s usually temporary. “It should go away after a few weeks,” says Gutierrez. Other side effects can include:

• Vomiting
• Abdominal pain
• Constipation
• Diarrhea
• Low blood sugar

The main GLP-1 drug risks include developing gallstones, pancreatitis, or more severe gastrointestinal problems, such as a bowel obstruction or gastroparesis (in which the muscles in the stomach don’t move food properly for digestion), although these are rare.

GLP-1 agonists are not recommended for people with a personal or family history of a rare genetic form of thyroid cancer or genetic syndrome called MEN2.