GLP-1 Receptor Agonists

GLP-1 receptor agonists are a type of incretin medication that people with type 2 diabetes can use to lower blood sugar levels.

How do GLP-1 receptor agonists work?

GLP-1 is a hormone (a natural chemical in the body) that is produced in the small intestine. It stimulates insulin secretion (which then allows cells to take up glucose) and inhibits glucagon secretion (which prevents more glucose from going into the bloodstream) to lower blood sugar levels. GLP-1 also slows stomach emptying, meaning that less glucose from food is released into the bloodstream. GLP-1s also increase satiety (how full you feel) after eating, which helps contributes to its weight loss properties.

Shorter-acting GLP-1s are particularly effective at lowering maximum glucose levels, whereas longer-acting GLP-1s have more balanced effects on lowering post-meal and fasting glucose levels.

Who uses GLP-1 receptor agonists?

GLP-1 agonists are most often used by people with type 2 diabetes to manage blood sugar levels. GLP-1s can be taken alone, or with metformin or other diabetes drugs.

GLP-1s are not approved by the FDA for people with type 1 diabetes. However, some healthcare professionals may prescribe GLP-1s off-label to those with type 1 diabetes.

What are the benefits?

GLP-1s are highly effective at lowering blood glucose and A1C levels. Often, GLP-1s are given with other medications as part of a combination treatment.
GLP-1s can lead to significant weight loss. Some GLP-1 drugs are sold as treatments for both diabetes and obesity. For example, Ozempic (diabetes drug) and Wegovy (obesity drug) both use a GLP-1 called semaglutide and differ only in dosage.
Some GLP-1s have been shown to lower the risk of heart disease and kidney disease.
GLP-1s by themselves have a low risk of hypoglycemia. However, hypoglycemia can become a serious risk if GLP-1s are taken alongside other medications that lower blood glucose, such as sulfonylureas or insulin.

What are the drawbacks?

Most GLP-1s are taken by injection. The only exception is Rybelsus, an oral medication (pill).
Common side effects include nausea, vomiting, and diarrhea. These generally decrease over time.
GLP-1s are more expensive than some other glucose-lowering medications, like sulfonylureas (SFUs), metformin, and TZDs. Patient assistance programs exist which can help people who meet eligibility criteria.