Rare Side Effect of Popular Weight Loss Drugs Revealed

Wegovy and Ozempic have quickly become very popular drugs to help people shed pounds.

Yet, both drugs — which contain semaglutide as their active ingredient — could pose significant dangers to people who consume them.

In a study that researchers from Massachusetts published on Wednesday, users of the drugs could develop a rare form of blindness.

The researchers started to look into whether use of either of the drugs is associated with people developing nonarteritic anterior ischemic optic neuropathy, or NAION, after receiving reports from some users. The study also points out that the reports came from people who used the drugs because they were obese or overweight and had type 2 diabetes.

The University of California, Davis Health, says that Ozempic is designed specifically for people who have diabetes, as it has lower levels of semaglutide. Wegovy, meanwhile, is just designed for weight loss and has higher levels of semaglutide. 

The researchers went back and analyzed data from nearly 17,000 patients who were seen by neuro-ophthalmologists at an academic institutions between December 1 of 2017 and November 30 of last year.

Some of these patients had type 2 diabetes, while others were just obese or overweight. The study also pointed out that some of the patients were put on medication with semaglutide, while others were put on other drugs that don’t contain the substance.

And none of the patients had a history of NAION.

The researchers then compared type 2 diabetes patients who had semaglutide drugs and those who did not, finding that those that had the substance posed a greater risk of developing NAION.

While the researchers investigated whether there was an association between NAION and semaglutide, they didn’t establish that the semaglutide actually caused NAION.

As they wrote in their report:

“As this was an observational study, future study is required to assess causality.”

Three of the people involved in the research were from the Harvard T.H. Chan School of Public Health and Harvard Medical School. The fourth person was from Boston’s Brigham and Women’s Hospital.

The study was published in The Journal of the American Medical Association.

NAION is basically an injury that causes blood to stop flowing to the optic nerve. It then quite often causes a sudden loss of vision in one eye, though it’s not painful. Patients typically notice it once they wake up in the morning.

One person who was invited to comment on the study wrote:

“NAION is a rare condition that affects between 2 to 10/100,000 people per year.”

In a statement, the U.S. Food and Drug Administration also issued a warning that people should not take semaglutide drugs that are marketed illegally online. The federal agency added that it was investigating some reports that there was fake Ozempic circulating throughout the country.

In May, Gallup estimated that about 15.5 million adults in the U.S. have used an injectable diabetes medication such as Ozempic for weight-loss purposes.