Ozempic and NAION Vision Loss: A Serious Eye Injury Linked to Semaglutide

Ozempic (semaglutide) has become one of the most widely used prescription drugs for Type 2 diabetes, and semaglutide medications are also used for weight loss. For many patients, these drugs are marketed as a modern solution for metabolic control. But as use has expanded, so have reports of serious complications. One of the most alarming injuries now associated with semaglutide use is Non-Arteritic Anterior Ischemic Optic Neuropathy (NAION), a condition that can cause sudden and permanent vision loss.

NAION is often described as an “eye stroke” because it involves a disruption in blood flow to the optic nerve. When the optic nerve is deprived of adequate blood supply, nerve fibers can be damaged quickly. What makes NAION particularly frightening is how abruptly it can appear. Many patients describe waking up to sudden vision changes in one eye, including blind spots, dim or blurred vision, or major loss of visual acuity, often without pain or warning. That pattern, characterized by a sudden, painless onset and significant visual deficits, is a hallmark of NAION’s clinical presentation.
What makes NAION different from many other drug side effects is the permanence. Once the optic nerve is injured, medical care is focused on diagnosis, risk-factor management, and protecting the other eye, but there is often no reliable treatment that restores lost vision. The result can be a lifelong impairment that affects work, independence, driving, reading, and everyday safety.

What Is NAION and Why Does It Cause Permanent Vision Damage?

NAION occurs when the optic nerve suffers ischemic injury, meaning a lack of oxygenated blood supply. The optic nerve is not just another “eye structure.” It is the cable that transmits visual information to the brain. When the blood supply fails, the injury can be immediate and irreversible.

From a patient’s perspective, the experience can be disorienting and devastating. A person may go to bed seeing normally and wake up unable to see clearly out of one eye. Others notice a shadow or missing section of their field of vision that does not go away. Even when the injury is “partial,” it can still create serious functional problems, including difficulties with depth perception and reduced contrast sensitivity, which make stairs, curbs, and nighttime navigation far more dangerous—especially in a place like New York City.

The Emerging Evidence and Regulatory Attention on Semaglutide and NAION

Concerns about semaglutide and NAION accelerated after a large matched-cohort study published in JAMA Ophthalmology reported an association between semaglutide prescriptions and an increased observed risk of NAION in certain patient cohorts. The authors emphasized that the findings show an association in observational data and that additional research is needed to evaluate causality, but the signal has been significant enough to draw sustained attention from clinicians, regulators, and litigators.

Regulators have also acted. In June 2025, the European Medicines Agency’s Pharmacovigilance Risk Assessment Committee (PRAC) concluded that NAION should be added to the product information for semaglutide as a “very rare” side effect and advised patients to seek medical attention for sudden vision loss or rapidly worsening eyesight. The PRAC position is important because it reflects a formal safety-review conclusion based on multiple sources of evidence, including clinical data and post-marketing surveillance.

Ozempic NAION Lawsuits and the Core Legal Allegations

Ozempic-related NAION claims generally focus on product safety, disclosure, and whether manufacturers provided adequate warnings to patients and healthcare providers. In plain terms, the legal question is often not just “Did the injury occur?” but “Was the risk properly communicated so patients could make informed decisions with their doctors?”
Plaintiffs commonly allege that the manufacturer failed to sufficiently warn about the risk of optic nerve injury, particularly where patients report sudden vision loss soon after starting semaglutide. These cases also explore medical causation questions, such as whether semaglutide could affect blood flow, vascular regulation, or metabolic pathways in ways that increase vulnerability to ischemic optic nerve events.

Because NAION can lead to permanent vision loss, these cases are often viewed as high-severity claims. Permanent impairment can change a person’s career options, reduce earning capacity, and require long-term monitoring and adaptation. In many cases, the emotional impact is inseparable from the physical injury: anxiety about further vision loss, fear about the other eye, and a profound loss of independence.

Federal Litigation Update: NAION MDL No. 3163

As these cases have increased nationwide, a separate federal multidistrict litigation has been created specifically for NAION claims involving GLP-1 receptor agonist drugs. The U.S. Judicial Panel on Multidistrict Litigation centralized these cases in the Eastern District of Pennsylvania before Judge Karen S. Marston as MDL No. 3163, noting related GLP-1 litigation already pending in the same court involving different alleged injuries.
MDL proceedings are designed to coordinate pretrial litigation, streamline discovery, and address common expert issues efficiently. They do not eliminate your individual claim, but they can shape how evidence is gathered, how bellwether trials proceed, and how settlement discussions develop.

What to Do After Sudden Vision Loss While Taking Ozempic

When vision changes suddenly, the first priority is medical care. Prompt evaluation by an ophthalmologist or neuro-ophthalmologist is critical for diagnosis and documentation. If NAION is confirmed or suspected, the medical record is usually one of the most important pieces of evidence in any future claim, because timing, exam findings, and diagnostic testing matter.

From a legal standpoint, documentation is often what makes or breaks pharmaceutical injury cases. A strong timeline typically includes the date semaglutide was prescribed, the date the medication was started, dose changes, onset of symptoms, emergency visits, ophthalmology notes, imaging results, and follow-up care. Pharmacy records can be particularly useful because they provide clear, third-party confirmation of fill dates and dosage history.
One important caution: no one should stop or change a prescribed medication without speaking to a qualified medical provider. The EMA’s June 2025 communication, for example, emphasizes seeking medical attention for sudden vision loss and indicates that semaglutide should be stopped if NAION is confirmed, but decisions still need to be made with a treating clinician based on the individual patient’s circumstances.

How Long Do I Have to File an Ozempic NAION Claim in New York?

In New York, many personal injury and product liability claims operate under a three-year limitations period, but the exact deadline can depend on how a claim is characterized and when it legally “accrues.” New York courts and public guidance materials commonly reflect a three-year period for product liability and many injury claims, which is why early legal evaluation matters when you’re dealing with a life-altering injury like vision loss.

If you are a New York resident or were treated in New York, it is especially important not to assume you have “plenty of time.” Medical records, prescribing histories, and specialist documentation are easier to obtain early, and the defense often scrutinizes delays to dispute causation.

FAQ: Ozempic, NAION, and Vision Loss Claims

Can Ozempic cause NAION?

The question is still being studied, but published research has reported an association between semaglutide prescriptions and increased observed risk of NAION in certain cohorts, and regulators in Europe have concluded NAION should be listed as a very rare side effect of semaglutide medicines. That combination, research signal plus regulatory action, is part of why these claims are receiving heightened attention.

What does NAION feel like?

Many patients report sudden, painless vision loss or a sudden change in visual field in one eye, sometimes noticed immediately upon waking. Others describe dimming, blurring, or missing areas of vision. The key feature is an abrupt change without the type of pain people often associate with serious eye problems.

Is NAION reversible?

In many cases, the injury is permanent or only partially improves. Medical care focuses on diagnosis, monitoring, and risk reduction for the other eye rather than on reliably restoring vision. This is one reason NAION is treated as a catastrophic injury in litigation when it results in lasting impairment.

Do I have a case if I had risk factors like diabetes or high blood pressure?

Possibly. Many NAION patients have underlying vascular risk factors. In litigation, the issue often becomes whether the drug increased the risk of the injury occurring when it did, whether warnings were adequate given the known or knowable risk, and whether the prescribing and injury timeline supports causation. These are fact-driven cases, and medical records matter.

What kind of compensation is available in an Ozempic NAION case?

If a claim is viable, damages may include medical costs, future monitoring and treatment, lost income, reduced earning capacity, and non-economic damages tied to permanent vision impairment and loss of independence. The value of a case depends on the severity of the vision loss, how it impacts work and daily life, and how strongly the evidence supports causation and failure-to-warn theories.

Important Note About Medical Decisions

This page is for informational purposes and is not medical advice. If you experience sudden vision loss or rapidly worsening eyesight while using semaglutide, seek medical attention immediately. Do not start, stop, or change any prescription medication without discussing it with your treating medical provider.

Contact Leandros A. Vrionedes

If you or a loved one suffered sudden vision loss or were diagnosed with NAION after using Ozempic, Wegovy, or another semaglutide medication, Leandros A. Vrionedes, P.C., can evaluate your situation, review your medical timeline, and explain your legal options under New York law. To schedule a free, confidential consultation, contact Leandros A. Vrionedes, P.C.