Wegovy Linked to 5x Higher Eye Stroke Risk vs Ozempic

Researchers are investigating potential eye-related risks associated with semaglutide medications.

A study published in the British Journal of Ophthalmology in March 2026 has drawn significant attention to the potential eye-related risks of semaglutide-based medications. The analysis, titled "Ischemic optic neuropathy with semaglutide: global observational analysis of sex- and formulation-specific risk," found that patients taking Wegovy may face nearly five times the risk of developing non-arteritic anterior ischemic optic neuropathy (NAION) — often referred to as an "eye stroke" — compared to those taking Ozempic. The findings have prompted professional organizations to issue guidance for clinicians navigating the growing body of evidence.

What the BMJ Study Found

The research team analyzed data from more than 30 million adverse event reports submitted to global pharmacovigilance databases, including the FDA's Adverse Event Reporting System (FAERS). According to the study's authors, Wegovy demonstrated the strongest statistical signal for ischemic optic neuropathy among the semaglutide formulations examined.

Key findings from the analysis include:

• The adjusted reporting odds of developing NAION were approximately five times higher for Wegovy users compared to Ozempic users.
• Male patients appeared to face roughly three times the risk of developing the condition compared to female patients.
• Although Ozempic generated a higher total number of NAION reports — likely due to its earlier FDA approval in 2017 and broader patient base — the statistical signal relative to total reports was substantially stronger for Wegovy.

The researchers noted that the difference in risk between the two formulations may be attributable to dosing. Wegovy, which is approved for chronic weight management, is prescribed at a maintenance dose of up to 2.4 mg per week. Ozempic, approved for type 2 diabetes management, is typically prescribed at doses ranging from 0.5 mg to 2.0 mg per week. Both medications contain the same active ingredient — semaglutide — but the higher dosing in Wegovy may amplify certain side effects, according to the study's authors.

Understanding NAION: What Is an "Eye Stroke"?

Non-arteritic anterior ischemic optic neuropathy occurs when blood flow to the front portion of the optic nerve is disrupted, causing sudden swelling and, in many cases, permanent vision loss. According to the North American Neuro-Ophthalmology Society (NANOS), NAION is the most common acute optic neuropathy in adults over the age of 50.

Symptoms of NAION typically include:

• Sudden, painless vision loss in one eye, often noticed upon waking
• A persistent gray or dark area in the upper or lower visual field
• Weakened color vision in the affected eye

Established risk factors for NAION include hypertension, diabetes, hyperlipidemia, obstructive sleep apnea, and a small optic disc anatomy sometimes called a "disc at risk." The condition has also been previously associated with certain medications, including those used for erectile dysfunction. NAION has no proven treatment, making prevention and risk factor management essential, according to the American Academy of Ophthalmology (AAO).

NANOS and AAO Issue Joint Consensus Statement

In May 2026, NANOS and the AAO published a joint consensus statement in the journal Ophthalmology to provide clinicians with evidence-based guidance. The statement addressed the accumulating research on the potential link between GLP-1 receptor agonists and NAION, offering several notable positions.

According to the consensus statement, existing literature suggests a "possible small increased risk" of NAION in patients taking semaglutide, but this risk has not been confirmed and causation has not been established. The organizations emphasized that the overall absolute risk of NAION remains low even among semaglutide users.

Notably, NANOS and the AAO diverged from the European Medicines Agency (EMA), which had previously recommended that patients immediately discontinue semaglutide upon a confirmed NAION diagnosis. The American organizations stated that they do not currently support a blanket policy of stopping GLP-1 receptor agonist therapy. Instead, they recommended a shared decision-making approach between patients and their healthcare teams — including ophthalmologists, endocrinologists, and primary care physicians — to weigh the risks and benefits of continuing or discontinuing treatment.

The statement noted that abruptly stopping semaglutide treatment programs could expose patients to significant health risks, particularly those managing obesity, poorly controlled diabetes, or cardiovascular comorbidities. Patients taking GLP-1 receptor agonists who experience sudden vision loss were advised to undergo immediate evaluation by an ophthalmologist.

Context from Earlier Research

The BMJ study builds on a body of research that has explored semaglutide's potential ocular effects. In July 2024, a retrospective matched cohort study published in JAMA Ophthalmology first reported a higher cumulative incidence of NAION among patients prescribed semaglutide compared to those on non-GLP-1 medications. That single-institution study generated considerable media attention and prompted calls for larger-scale investigation.

A subsequent 2025 analysis using the TriNetX global database also identified an increased risk of NAION in patients with diabetes taking semaglutide, although notably, the association appeared primarily after two to four years of use. Other studies published during this period suggested a more modest increase in risk than the initial 2024 report indicated.

Researchers across these studies have consistently stressed important methodological limitations. The adverse event reporting databases used in such analyses rely on voluntary submissions and cannot control for confounding variables such as pre-existing vascular disease, concurrent medications, or anatomical predispositions. These observational designs can identify statistical signals but cannot establish causation. Meanwhile, analyses of randomized, placebo-controlled clinical trials have not consistently found an increased incidence of NAION in participants receiving GLP-1 receptor agonists compared to placebo.

The EMA classified NAION as a "very rare" potential side effect of semaglutide in mid-2025, and the World Health Organization has also evaluated the evidence. Product labeling for both Ozempic and Wegovy has been recommended for updates to reflect these findings. Individuals considering GLP-1-based therapies such as semaglutide or tirzepatide options may wish to discuss these findings with their prescribing physician, particularly if they have existing risk factors for optic neuropathy.

What This Means for Patients

For the millions of patients currently using semaglutide for weight management or diabetes, the emerging data on NAION represents a nuanced clinical picture. The absolute risk of developing the condition appears to remain low, but the dose-dependent pattern identified in the BMJ study — and the stronger signal associated with Wegovy's higher dosing — suggests that clinicians and patients should factor eye health into their ongoing treatment discussions.

The NANOS-AAO consensus statement underscored that the cardiovascular, metabolic, and weight management benefits of GLP-1 receptor agonists remain well-documented and, for many patients, may outweigh the small potential ocular risk. However, the organizations encouraged heightened vigilance: patients should be counseled about the symptoms of NAION, and any episode of sudden, painless vision loss should be treated as a medical urgency requiring immediate ophthalmologic evaluation.

Patients with pre-existing risk factors for NAION — including hypertension, diabetes, sleep apnea, and a crowded optic disc — may warrant closer monitoring, according to the consensus statement. Those interested in exploring whether GLP-1-based treatments are appropriate for their health profile can check if they qualify through a clinical evaluation.

Clinicians may also want to consider establishing baseline eye examinations for patients initiating high-dose semaglutide therapy, particularly those with multiple vascular risk factors. While no formal screening guidelines have been issued, several neuro-ophthalmology specialists quoted in commentary accompanying the BMJ study suggested that documenting optic disc anatomy and visual field status before treatment could help identify patients at elevated risk and facilitate faster diagnosis if symptoms develop.

As research continues, prospective studies and long-term clinical data will be essential to clarify whether the association between semaglutide and NAION reflects a true causal relationship or a statistical artifact amplified by reporting patterns and confounding variables. Until then, informed shared decision-making between patients and their healthcare providers remains the recommended approach.

This article is for informational purposes only and is not medical advice. Consult your healthcare provider before starting any weight loss medication or treatment.