The U.S. Food and Drug Administration (FDA) has mandated that manufacturers of GLP-1 class medications used for weight loss and diabetes management—specifically Ozempic, Wegovy, Mounjaro, and Zepbound—add information regarding the risk of serious eye damage to the “Warnings and Precautions” section of their prescribing labels.
This pertains to a rare condition known as non-arteritic anterior ischemic optic neuropathy (NAION). The condition reduces blood flow to the front part of the optic nerve, manifesting as sudden, painless vision loss. In some cases, the process may cause irreversible visual impairment.
The FDA made this decision based on a comprehensive analysis of clinical, post-marketing, and observational data, including a large-scale study published in 2025 that examined the medical histories of up to 175,000 patients.
It is worth noting that the link between GLP-1 medications and sudden vision loss requires further research. Endocrinologist Nino Zavrashvili spoke in detail with Medscriptum regarding current guidelines, reliable clinical studies, and the challenges and potential complications encountered in clinical practice.
What is NAION (non-arteritic anterior ischemic optic neuropathy), and why did it draw the FDA’s attention in relation to GLP-1 medications? According to the new FDA guidelines, the warning labels on these medications must state that a rare vision-related complication could cause sudden blindness.
Optic neuropathy is the most common disease of the optic nerve in patients over the age of 50.
Non-arteritic anterior ischemic optic neuropathy (NAION) is the most prevalent form of ischemic optic neuropathy. It is an acute injury to the optic nerve that typically presents in one eye as painless vision impairment or vision loss. NAION is the most common optic neuropathy in the elderly population. It generally develops spontaneously, mostly in individuals with atherosclerosis or its contributing factors, such as diabetes mellitus, hypertension, obesity, sleep apnea, kidney disease, and others. Certain medications may also increase the risk of developing this condition.
Given the FDA’s decision, how high is the actual risk of this rare eye condition among users of Ozempic, Wegovy, Mounjaro, and Zepbound? Have you encountered similar cases in your practice, and what factors contributed to them?
Fortunately, this risk is very low. To put it into perspective, according to data from a major Denmark-Norway study involving over 60,000 patients with diabetes mellitus, the total number of NAION cases during treatment with GLP-1 agonists was 32. This demonstrates that the condition is rare. Within the same cohort, the incidence of new NAION cases was 2.19 per 10,000 in the GLP-1 treatment group, compared to 1.18 per 10,000 in the group receiving other glucose-lowering treatments. While this indicates a statistically significant relative risk, the absolute risk remains low—not only according to this specific study, but also according to other reliable clinical studies.
Prior to prescribing any treatment, including GLP-1 agonists, it is essential to take a detailed medical history of the individual patient, review diagnostic results, and conduct a thorough evaluation of potential risks versus benefits.
Is there already a confirmed causal link between GLP-1 medications and vision loss, or is this currently only a statistical association that requires further clinical trials?
A causal link has not been established. Indeed, it remains an association. In the majority of studies and throughout clinical practice, we observe neuroprotective effects from these medications, as well as a reduced risk of cardiovascular disease, diabetes, arthritis, liver and kidney diseases, and other conditions.
Which patient group has the highest risk of developing NAION while undergoing GLP-1 therapy?
As mentioned earlier, the risk of NAION is higher in the elderly population who have one or more risk factors for atherosclerosis. By atherosclerosis, we mean damage to the inner walls of the blood vessels, the risk of which is driven by chronic conditions such as diabetes, hypertension, chronic kidney disease, obesity, and so forth.
What specific signs and symptoms should patients pay attention to?
NAION most frequently manifests as painless vision loss, usually in one eye. If such symptoms occur, it is imperative to contact a doctor immediately.
Is the FDA’s recommendation—that vision-related risks be included among the warnings for GLP-1 medications—effectively a cautionary signal to the medical community to prescribe these drugs based on deeper evaluation and research?
Undoubtedly, this factor must be taken into consideration. As with prescribing any other medication, it is critically important to collect a detailed medical history, conduct thorough examinations, and offer treatment to the patient only after an objective assessment of the risks and benefits.
Currently, the criteria for treatment with GLP-1 agonists include obesity (a Body Mass Index greater than 30) or being overweight with associated risk factors or complications, such as diabetes mellitus, elevated cholesterol or blood pressure, cardiovascular disease, and others.
Furthermore, this treatment must go hand in hand with the principles of a healthy, balanced diet and regular physical activity within the limits of the patient’s physical capabilities.
