Weight-loss injections and vision loss: FDA lists signs to watch for

The U.S. Food and Drug Administration (FDA) has issued its latest warning about possible effects on vision from weight-loss injections. According to the agency, drugs that are increasingly being used for weight loss, including Ozempic, Mounjaro and Wegovy, may be linked to an increased risk of ischemic optic neuropathy, a condition that affects the eye.

After reviewing 126 clinical studies involving 134,000 people, the FDA identified approximately six cases per 100,000 users of GLP-1 drugs. Based on these findings, the agency is calling for this side effect to be included in the information leaflets accompanying the medications.

Ischemic optic neuropathy occurs when blood flow to the front part of the optic nerve is reduced. As a result, vision can be lost suddenly, and the damage may be permanent.

For people using these injections, one sign may be sudden vision loss in one eye. Other signs include blurred vision, dark spots in the field of vision, difficulty distinguishing colors and reduced visual acuity.

The FDA explains that the absence of pain may mean patients do not notice the problem immediately. Some may notice the change only after waking up in the morning.

People taking injections or oral medications for weight loss are advised to see an eye specialist without delay for an assessment if they notice sudden changes in their vision.

The FDA also stresses that patients should not decide on their own to stop taking the medications, but should do so only after consulting a doctor.