People taking weight-loss drugs say they are losing their sight. Science is trying to figure out why
Physicians have warned that a small percentage of patients taking popular weight loss and diabetes medications have experienced vision loss. However, they say that they have not established a direct link between the condition and taking the drugs.
Several patients using brand-name drugs like Ozempic, Wegovy, Mounjaro, and Zepbound experienced problems with their eyes, researchers said.
Seven of the nine patients their study focused on had a loss of blood flow to the optic nerve, and one had inflammation of the optic nerve head. Another had a blind spot in their vision, and some had atypical symptoms of the conditions.
The optic nerve is an essential part of a person’s vision, carrying signals from the eyes to the brain. Loss of blood flow damages the nerve and results in sudden partial vision loss that is usually permanent.
The patients were adults in their 50s and 60s who have diabetes or obesity, in addition to other cardiovascular comorbidities that can also cause vision issues.
“We’re trying to elucidate if being on these drugs can increase your risk,” Norah Lincoff, professor of neurology at the University of Buffalo, said in a statement.
Lincoff is a co-author of the study published late last month in the journal JAMA Ophthalmology.
Previous studies have also documented vision-related problems in patients using the popular drugs, and a July study from Mass Eye and Ear found that some people prescribed semaglutide have a higher risk of developing a form of blindness.
“To be perfectly clear, I would not take my findings and use them to recommend that patients stop taking their medications,” Dr. Joseph Rizzo, a Mass General Brigham opthalmologist, said in September. “Our finding was really the first possible significant negative finding with these drugs. It may just merit extra caution in the consideration between doctors and patients about who may use this medicine.”
Other classes of drugs have also been found to cause optic nerve disease in some patients, the recent study’s authors noted.
People should not randomly decide to go off weight loss drugs, but should be cautious when taking them, possibly stopping the medication or adjusting the dosage if they experience vision loss.
Still, the researchers say that a reduction in blood glucose levels from the drugs may put people at higher risk. Fluctuations in blood sugar can affect vision temporarily for all diabetic patients, and even those not on the drugs may have blurring for an hour or two when their blood sugar levels change.
Ozempic, Wegovy, Mounjaro, and Zepbound all lists change in vision as a possible side effect on their websites.
A spokesperson for Novo Nordisk, which makes Ozempic and Wegovy, told The Independent in an email on Wednesday that loss of blood flow to the optic nerve — also known as non-arteritic anterior ischemic optic neuropathy — is not an adverse drug reaction for Ozempic, Rybelsus, and Wegovy, as per the approved labels.
“After a thorough evaluation of studies from the University of Southern Denmark and Novo Nordisk’s internal safety assessment, Novo Nordisk is of the opinion that the benefit-risk profile of semaglutide remains unchanged,” they said.
“Novo Nordisk, on its part, has conducted an analysis across randomized controlled clinical trials with GLP-1 receptor agonists, including a blinded ophthalmologist evaluation to confirm [the] diagnoses. These data do not suggest a causal relationship between GLP-1 RA use and [the loss of blood flow],” the spokesperson noted.
“The message to the patient is that we are still investigating if these drugs put them at higher risk of ischemic optic nerve damage,” Lincoff said. “And the message to the primary care provider is, if a patient on one of these medications calls you and says that there is blurring or vision loss, have them see their ophthalmologist as soon as possible. Don’t wait. Maybe it’s a fluctuation in glucose or it could be something more serious.”
