In people without diabetes, the balance of blood sugar (glycemic homeostasis) is maintained by several hormones, including insulin, glucagon and amylin. Incretin hormones like GLP-1 also play a crucial role. When you eat, the cells in your intestines release these incretin hormones, which then stimulate the pancreas to produce insulin. This process is mainly triggered by eating glucose – not by receiving it. However, in people with impaired glucose tolerance or those with type 2 diabetes, this mechanism can be disrupted and such an event results in high blood sugar levels (hyperglycemia).
How Do GLP-1 Agonists Work to Prevent High Blood Glucose Levels?
GLP-1 receptor agonists mimic the action of the natural hormone GLP-1. They work by increasing the production of insulin (stimulate the pancreas to produce more insulin), slow down emptying in the stomach and reducing sugar release from the liver to keep your blood sugar levels in check.
How are GLP-1 Agonists Taken?
Most GLP-1 receptor agonists are taken mostly by injection, but there is one, oral semaglutide, which is available in pill form.
With injectable GLP-1 Agonists, they come in easy-to-use pen injection devices with small needles. Some pens are single-use with a premeasured dose, while others allow you to adjust the dose. You inject it just under the skin in areas like your upper arm, stomach or thigh. Some GLP-1 RAs are taken once or twice daily, while others are administered once weekly. Your doctor will start you on a low dose and gradually increase it to the right amount for your needs.
What are the different types of GLP-1 RAs?
GLP-1 receptor agonists (GLP-1 RAs) are a class of medications used to manage type 2 diabetes by mimicking the effects of the naturally occurring hormone GLP-1. While all GLP-1 RAs function similarly in the body, they can be categorized into two main types: short-acting and long-acting.
Short-acting GLP-1 RAs have a duration of action lasting less than a day and they primarily help control blood sugar levels after meals. Some of the short-acting GLP-1 RAs approved for use in the United States are:
Exenatide (Byetta)
Oral Semaglutide (Rybelsus)
Lixisenatide (Adlyxin)
Long-acting GLP-1 RAs, on the other hand, work for a full day or even a week. The long-acting GLP-1 RAs approved in the US are:
Semaglutide (Ozempic)
Liraglutide (Victoza)
Exenatide Extended-Release (Bydureon)
Dulaglutide (Trulicity)
Are GLP-1 RAs Effective as Treatment for Type 2 Diabetes?
GLP-1 RAs are found to be very effective at lowering blood glucose levels both during fasting periods and after meals. And unlike some other diabetes medications, they have a lower risk of causing hypoglycemia (low blood sugar).
New research suggests that some GLP-1 RAs may also benefit the heart health and kidney function in people who have diabetes. Medications like Victoza, Ozempic, Rybelsus, and Trulicity have been linked to significant reductions in heart attacks in individuals with diabetes. Moreover, studies have shown that certain GLP-1 RAs can improve kidney outcomes compared to a placebo.
Are GLP-1 Agonists Safe for People with Type 2 Diabetes?
The FDA has approved GLP-1 agonists for managing type 2 diabetes due to their effectiveness in lowering blood sugar levels. GLP-1 RAs stimulate insulin release and reduce blood glucose after meals by mimicking the GLP-1 hormone found in the intestines. However, these drugs are not recommended for individuals with a personal or family history of medullary thyroid cancer or multiple endocrine neoplasia. While lab studies have shown a link between GLP-1 RAs and thyroid tumors in rats, the long-term risk to humans remains uncertain and requires further investigation.