The U.S. Food and Drug Administration (FDA) issued a warning Friday that a widely used new class of type 2 diabetes drugs may cause high levels of blood acids dangerous enough to put people in the emergency room.

The new class of type 2 diabetes drugs are a group of oral medications called SGLT2 inhibitors, which work by helping the kidneys to lower blood glucose levels and blood sugar to be secreted in the urine. This prevents the kidneys from reabsorbing glucose back into the blood, thereby lowering blood glucose levels. A possible side effect of these drugs is actually weight loss.

SGLT2 inhibitors are recommended for people with type 2 diabetes who have high blood glucose levels regardless of being on medications like metformin and insulin.

However, there are certain side effects that are potentially dangerous. The FDA says the drugs may cause diabetic ketoacidosis, which results from a shortage of insulin.

Diabetic ketoacidosis is a serious condition that causes the body to produce high levels of blood acids called ketones. The condition occurs when your body is not able to produce enough insulin which normally helps glucose enter the body’s cells. Without the right amount of insulin, the body starts to break down fat as an alternate fuel source for insulin. This, in turn, causes a buildup of toxic acids in the blood called ketones.

Under normal circumstances, those at highest risk for diabetic ketoacidosis include people who have type 1 diabetes, are younger than age 19, and frequently miss insulin doses. Diabetic ketoacidosis can also occur in people who have type 2 diabetes, although it is less common.

The FDA revealed that over the last year, about 20 patients taking this new class of diabetes drugs ended up in emergency room due to diabetic ketoacidosis.

Other side effects can include genital and urinary tract infections, hypoglycemia, and possibly liver damage, breast cancer and bladder cancer. Long-term side effects have only been studied in clinical trials and are not yet confirmed. 

The new drugs are currently sold as Astra Zeneca’s Farxiga (dapagliflozin), Johnson & Johnson’s Invokana (canagliflozin), and Eli Lilly/Boehringer Ingleheim’s Jardiance (embagliflozin).

Dr. Samadi is a board-certified urologic oncologist trained in open and traditional and laparoscopic surgery and is an expert in robotic prostate surgery. He is chairman of urology, chief of robotic surgery at Lenox Hill Hospital and professor of urology at Hofstra North Shore-LIJ School of Medicine. He is a medical correspondent for the Fox News Channel's Medical A-Team and the chief medical correspondent for am970 in New York City. Learn more at roboticoncology.com. Visit Dr. Samadi's blog at SamadiMD.com. Follow Dr. Samadi on Twitter and Facebook.