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Updated April 2026 — MDL 3163 | Harvard Study Confirmed

NAION Lawsuit: Sudden Vision Loss Linked to Ozempic, Wegovy & GLP-1 Drugs

If you were diagnosed with NAION or experienced sudden vision loss after taking Ozempic, Wegovy, Mounjaro, or another GLP-1 drug, you may be eligible for significant compensation. A Harvard Medical School study found a 4-8x elevated NAION risk.

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What Is the NAION Lawsuit?

The NAION lawsuit — consolidated as MDL 3163 in the Eastern District of Pennsylvania — involves claims that GLP-1 receptor agonist medications caused patients to develop Non-Arteritic Anterior Ischemic Optic Neuropathy (NAION), a form of sudden, often permanent vision loss.

The litigation was significantly accelerated by a July 2024 study published in JAMA Ophthalmology by researchers at Harvard Medical School. Using a database of 60 million patient records (TriNetX), the study found that semaglutide users (Ozempic, Wegovy) had an incidence of 8.9 NAION cases per 10,000 patients — compared to just 1.8 per 10,000 in non-users, representing approximately a 4-8x elevated risk.

NAION Lawsuit at a Glance

  • MDL 3163 — Eastern District of Pennsylvania, Judge Karen Marston
  • Harvard study (JAMA Ophthalmology 2024) — 4-8x elevated NAION risk in semaglutide users
  • Drugs involved: Ozempic, Wegovy, Mounjaro, Trulicity, Saxenda, Rybelsus, Victoza, Zepbound
  • Litigation is in early stages — now is the time to file
  • No upfront cost — attorneys work on contingency

What Is NAION?

NAION — Non-Arteritic Anterior Ischemic Optic Neuropathy — is a condition where the blood supply to the optic nerve is suddenly reduced or cut off, causing rapid, often permanent vision loss. Key facts:

  • Typically affects vision in one eye, though it can progress to the other
  • Onset is sudden and painless
  • Vision loss is often permanent — there is no FDA-approved treatment to reverse it
  • Symptoms: sudden dark spots, loss of peripheral vision, blurring, complete loss in affected eye
  • Diagnosis is typically confirmed by an ophthalmologist via visual field testing and optic nerve imaging

The life impact of NAION can be severe: inability to drive, difficulty reading, loss of employment, and significant emotional distress.

The Harvard Study: What the Science Shows

Published in JAMA Ophthalmology in July 2024, the Hathaway et al. study from Harvard Medical School analyzed 60 million patient records through the TriNetX health network. Key findings:

  • Semaglutide users (Ozempic, Wegovy): 8.9 NAION cases per 10,000 patients
  • Non-semaglutide users: 1.8 NAION cases per 10,000 patients
  • This represents an approximately 4-8x elevated risk depending on patient subgroup
  • The association persisted after controlling for diabetes, obesity, and cardiovascular risk factors

Despite this published research, Novo Nordisk has not updated US drug labels to warn of the NAION risk — a central argument in the current litigation. Plaintiffs allege the company knew or should have known about the risk and failed to warn.

Which Drugs Are Involved?

The NAION lawsuit encompasses all major GLP-1 receptor agonists:

Novo Nordisk Drugs

  • Ozempic (semaglutide) — weekly injection for type 2 diabetes
  • Wegovy (semaglutide) — weekly injection for weight loss
  • Rybelsus (semaglutide) — oral tablet
  • Victoza (liraglutide) — daily injection
  • Saxenda (liraglutide) — daily injection for weight loss

Eli Lilly Drugs

  • Mounjaro (tirzepatide) — weekly injection for type 2 diabetes
  • Zepbound (tirzepatide) — weekly injection for weight loss
  • Trulicity (dulaglutide) — weekly injection

Do You Qualify for the NAION Lawsuit?

Qualifying Criteria

  • You were prescribed a GLP-1 medication listed above
  • You were diagnosed with NAION or sudden vision loss confirmed by an ophthalmologist
  • You are within your state's statute of limitations

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Frequently Asked Questions

What is the NAION lawsuit?
The NAION lawsuit (MDL 3163) involves claims that GLP-1 drugs (Ozempic, Wegovy, Mounjaro, etc.) increase the risk of NAION — sudden, often permanent vision loss. A Harvard study found 4-8x elevated risk in semaglutide users.
Who qualifies for a NAION lawsuit?
You may qualify if you took a GLP-1 medication and were diagnosed with NAION or sudden vision loss confirmed by an ophthalmologist, and are within your state's statute of limitations.
What is NAION?
NAION (Non-Arteritic Anterior Ischemic Optic Neuropathy) is sudden vision loss caused by reduced blood flow to the optic nerve. It's typically painless, often permanent, and has no FDA-approved reversal treatment.
Which GLP-1 drugs are linked to NAION?
The Harvard study focused on semaglutide drugs (Ozempic, Wegovy) from Novo Nordisk. The MDL also includes Eli Lilly's tirzepatide drugs (Mounjaro, Zepbound), as well as Trulicity, Saxenda, Rybelsus, and Victoza.

→ Full GLP-1 Vision Loss Lawsuit Guide | About NAION | MDL 3163 Updates

As Referenced In
Did Ozempic, Wegovy, or another GLP-1 drug cause your vision loss? You may qualify for compensation. Check Eligibility →