Injected Diabetes Medication

Drugs in this class mimic the action of glucagon-like peptide-1 (GLP-1), a hormone that triggers insulin production after a meal.


Byetta acts only when blood glucose levels are high. This is an important difference from other diabetes drugs, which often cause hypoglycemia by triggering insulin secretion even when blood glucose levels are low.

Byetta is a synthetic version of a protein derived from the saliva of a venomous lizard known as the Gila monster. It is an injected medication that is taken in addition to metformin and/or a sulfonylurea. In one study, nearly half of individuals who had previously been unable to control their blood glucose with oral medication reduced their HbA1c levels to 7 percent or lower after taking Byetta for 30 weeks. Byetta users also lost 3–6 lbs on average.

Byetta is not recommended for people with type 1 diabetes, severe kidney disease, or severe gastrointestinal disease. Nausea is the most common side effect. Vomiting and diarrhea may also occur. Because Byetta slows the absorption of oral drugs, you may need to take certain medications at least one hour before an injection of Byetta.

Other Injected Diabetes Medications

The U.S. Food and Drug Administration (FDA) approved albiglutide (Tanzeum) subcutaneous injection in April 2014 and dulaglutide (Trulicity) once-a-week subcutaneous injection in September 2014 to improve glycemic control in adults with type 2 diabetes. These medications can be used with diet and exercise - alone or combined with other treatment regimens like metformin, glimepiride, pioglitazone, and insulin.

In clinical studies, people taking albiglutide and dulaglutide showed improvements in HbA1c levels - indicating better blood sugar control. As with Byetta, these drugs are not used to treat type 1 diabetes. They also are not used in people with diabetic ketoacidosis (high levels of ketones in the blood or urine), or as a first-line treatment for type 2 diabetes that cannot be managed with diet and exercise.

Albiglutide and dulaglutide carry boxed warnings and should not be used in people with a personal or family history of medullary thyroid carcinoma or multiple endocrine neoplasia syndrome type 2, as the drugs may increase the risk for thyroid gland tumors. Further post-marketing studies - required by the FDA - are being conducted.

Common side effects of Tanzeum include diarrhea, nausea, and reactions at the site of injection. Trulicity may cause abdominal pain, nausea and vomiting, diarrhea, and loss of appetite.

Non-Insulin Injectables Update

According to our sister publication Diabetes Focus (Summer, 2015), when oral medication isn't enough to control blood sugar, your doctor may prescribe an injectable medication. These new drugs mimic the action of glucagon-like peptide-1 (GLP-1) a hormone that stimulates insulin release after eating.

These medications don't cause low blood sugar, as they only act when blood glucose is high. They're not used for people with severe kidney disease or severe gastrointestinal disorders.

The GLP-1 medications available currently are exenatide, pramlintide, and liraglutide. Some are injected before a meal, but others are injected at any time of day, once or twice daily, or even once weekly. Exenatide can interfere with the absorption of other medications, so you may need to space them apart.

All GLP-1 drugs can reduce appetite and cause significant weight loss. Nausea is the most common side effect; vomiting and diarrhea can also occur. These are relatively new medications, so long-term studies aren't in yet, but there are some concerns that liraglutide may increase the risk of pancreatitis and thyroid cancer.

Updated by Remedy Health Media

Publication Review By: Written by: Christopher D. Saudek, M.D.; Simeon Margolis, M.D., Ph.D.

Published: 20 Apr 2009

Last Modified: 14 May 2015