GLP-1 Drugs and Vision Loss Complaints: New Class Action Lawsuit Platform to be Established in the US — What is NAION?

The "Blindness" Lawsuit Moves Forward in a "Separate Frame"—A New Class Action Lawsuit Over GLP-1 Drugs

Regarding GLP-1 drugs (such as Ozempic, Wegovy, Saxenda, Trulicity, etc.), which have become globally popular as a trump card for obesity and diabetes treatment, now claims of **"lost vision" or "went blind" are rapidly gaining presence in court. In the United States, lawsuits are being filed by patients claiming partial or total vision loss, and to address the complex issues, the federal Judicial Panel on Multidistrict Litigation (JPML) has decided to **centralize lawsuits related to non-arteritic anterior ischemic optic neuropathy (NAION) as a new MDL**.Reuters

It is important to note that "centralization" does not immediately imply that a causal relationship has been established. An MDL is a framework that gathers similar lawsuits scattered across the nation into one federal court to streamline evidence disclosure and expert testimony. In other words, the court has determined that it is more rational to handle these cases collectively due to common issues, rather than declaring a medical conclusion.

What Has Been Decided: A New Optic Nerve Disorder MDL Separate from the Existing "Gastrointestinal Disorder MDL"

According to reports, the newly centralized lawsuits claim that "GLP-1 drugs can cause non-arteritic anterior ischemic optic neuropathy (NAION)." The plaintiffs argue that the necessary medical discussions, evidence, and experts differ from those in the existing MDL concerning gastrointestinal disorders (such as gastroparesis), and the judicial panel supports this. The new MDL will be handled in the federal court in Philadelphia and will proceed under the same judge, Karen Marston, as the existing gastrointestinal disorder MDL, but the proceedings will progress in a **"separate structure."**

The number of cases cannot be ignored. While there are about 30 federal lawsuits and over 40 state court cases concerning optic nerve disorders, the MDL regarding gastrointestinal disorders is said to accumulate around 3,000 lawsuits.Reuters

What is NAION: Sudden "Blood Flow Trouble in the Optic Nerve"

NAION is often described as a condition that causes vision impairment due to reduced blood flow to the optic nerve. A characteristic issue is sudden vision loss, and treatment can be difficult in some cases. Research papers also categorize NAION as "vision loss due to reduced blood flow to the optic nerve," and it is noted to occur more frequently in people with backgrounds such as diabetes, obesity, and hypertension.JAMA Network

This "condition originally associated with diabetes and obesity" becomes even more complex in discussions of causality when intertwined with GLP-1 drugs used for diabetes and obesity treatment. Whether the drug is the cause or if it is an extension of underlying conditions and coexisting risks (such as blood pressure, lipids, sleep apnea, etc.)—this is the main point of contention in both trials and research.

The Current State of Science: While a Link is Suggested, Conclusions are Not Unified

The background pushing this theme includes several observational studies. For example, a study in JAMA Ophthalmology (2024) suggests a link between semaglutide and NAION, but concludes that "additional research is needed to confirm causality" as it is an observational study.JAMA Network

Furthermore, a large cohort study published in JAMA Network Open (2025) analyzed electronic medical record data of patients with type 2 diabetes and found that semaglutide or tirzepatide was associated with an increased risk of optic nerve disorders such as NAION, while also clearly stating that **"the overall risk is low."** Even if a link appears to exist, whether it is frequent enough for individuals to be immediately fearful is a separate issue.JAMA Network

How to interpret this "suggestion of a link" and "low absolute risk" can easily divide public opinion, investors, and healthcare providers. Moreover, GLP-1 drugs can offer significant benefits to some patients, including not only weight loss but also the suppression of cardiovascular events. This is why the interpretation of "scary news" is so crucial.

Regulatory Movements: In Europe, Classified as a "Very Rare" Side Effect

Notably, regulatory updates are worth attention. In Europe, reports on EMA evaluations indicate that NAION is treated as a **"very rare"** side effect in semaglutide formulations (such as Ozempic, Wegovy, Rybelsus), with a direction to reflect this in package insert information. The frequency is reported as "up to about 1 in 10,000 per year."Reuters

On the other hand, manufacturers reportedly maintain the position that the overall benefit-risk assessment remains favorable.Reuters

The fact that regulatory authorities are acknowledging a "non-zero possibility" while not steering towards a complete halt in use symbolizes the current balance.

How Will the Trial Proceed: The "Next Phase" Implied by MDL

The MDL process generally leads to the following three outcomes:

• Evidence disclosure, internal documents, and expert testimony are consolidated, allowing issues to be explored more quickly than in individual lawsuits

• Representative cases for **bellwether (trial trials)** become apparent

• As a result, the direction towards settlement (or dismissal) becomes more easily shared with the market

However, optic nerve disorders are often seen as having "many background factors and strong individuality" compared to gastrointestinal disorders, and proving causality may not be easy. The plaintiffs argue that "warnings were insufficient," while the companies counter that "risks are known and regulated" and "design changes cannot be made without FDA approval."Reuters

Reactions on Social Media: Fear, Skepticism, and "Still Using" Divide

This news is a hot topic on social media, with noticeable temperature differences such as the following:

1) Suspicion that "Abuse or Misuse is the Cause"
On Reddit, posts view the lawsuits as "a result of abuse or misuse," with a narrative leaning towards personal responsibility.Reddit

2) "The Risks of Diabetes and Obesity are Also Serious. Don't Just Blame the Drug"
Conversely, since diabetes and obesity themselves pose significant health risks, there is strong opposition to focusing solely on the drug's side effects.Reddit

3) "Insurance Rejects Mounjaro and Forces Ozempic... It's Contradictory"
Frustration with the system also emerges, highlighting the twists in insurance coverage and prescription policies, with voices claiming "it's not that simple on the ground."Reddit

4) "Even if Warned, People Won't Stop"—A Realism Similar to Dependency
A nihilistic realism is also observed, stating that "people won't stop even if there are health risks."Reddit

5) "Let's Discuss with Data"—A Group Seeking Evidence Over Emotion
There is a clear attitude of seeking discussions on frequency, comparison, and causality rather than individual anecdotes, with a sentiment of "let's talk after showing the numbers."Reddit

6) In User Communities, the Focus is on "Monitoring"
In communities of GLP-1 users, practical topics such as "not missing changes in vision" and "the relationship with changes in blood pressure and weight" are more common than fear-mongering. Posts mention "nighttime blood pressure drops" as advice from ophthalmologists, and there are claims of experiencing NAION personally (though truth and generalization cannot be confirmed).Reddit

The Optimal Solution for Recipients: Avoiding "All or Nothing"

The difficulty of this news lies in the fact that "scary" and "effective" coexist. While GLP-1 drugs bring benefits to many, the emergence of even rare but severe side effect suspicions can quickly shake societal acceptance.

Realistically,

• causality is not confirmed (research suggests, but is mainly observational with limitations)JAMA Network

• However, regulation and courts have entered a stage where it is **"an issue that cannot be ignored"**Reuters
  Holding these two points simultaneously is likely the most stable perspective.

※This article is for general informational purposes and is not medical advice. If you are taking medication, do not stop on your own judgment, and consult a medical institution if you have symptoms.