FDA warns GLP-1 drugs may cause rare vision loss

FDA adds vision warning to blockbuster drugs

The Food and Drug Administration announced Monday that all GLP-1 drugs, including Ozempic, Wegovy, Zepbound and Mounjaro, will carry new warnings about a rare vision-loss side effect.

The condition and how it works

The eye condition, known as non-arteritic anterior ischemic optic neuropathy or NAION, can cause significant vision loss. It is caused by decreased blood flow to the optic nerve, although the underlying cause is not understood.

How the FDA discovered the risk

FDA scientists began investigating after a two thousand twenty-four medical paper tied the condition to patients taking semaglutide, the active drug in Novo Nordisk's Ozempic and Wegovy.

The risk is real but rare

An FDA analysis of more than one hundred twenty-five clinical trials found the problem occurred in roughly six of every one hundred thousand patients who took a GLP-1 for at least one year.

Vision loss may be permanent

Symptoms include blurred vision, blind spots, distorted colors and other visual disturbances. Dr. Joseph Rizzo, a neuro-ophthalmologist at Massachusetts Eye and Ear, said vision loss from the condition tends to be irreversible and can become…

“Usually when you lose vision, although there may be some mild degree of improvement, it's usually not a large degree of improvement.”

Drugmakers defend their medicines

Novo Nordisk said it continues to believe the data do not establish a cause-and-effect relationship and remains confident in the benefit-risk profile.

“The medicines have really been profoundly beneficial to a large number of people.”