What Is NAION?
Non-arteritic anterior ischemic optic neuropathy (NAION) is caused by sudden loss of blood flow to the optic nerve, resulting in painless, often irreversible vision loss. It typically affects one eye at a time and can range from mild visual field loss to near-total blindness. NAION is the most common cause of sudden optic nerve-related vision loss in adults over 50.
The Semaglutide-NAION Connection
A July 2024 JAMA Ophthalmology study found semaglutide users had dramatically elevated NAION risk: 8.9% among diabetic patients (vs 1.8% non-semaglutide) and 6.7% among weight-loss patients (vs 0.8%). A Danish/Norwegian cohort study of 424,000+ patients confirmed that semaglutide more than doubled NAION risk compared to SGLT2 inhibitors.
The Failure-to-Warn Gap
The European Medicines Agency (EMA) required NAION warnings on European semaglutide labels in August 2024. Novo Nordisk has not added equivalent warnings to U.S. labels — creating a clear failure-to-warn argument. A separate NAION MDL (3163) was established in December 2025.
Legal Claims for NAION
NAION claims are among the highest-value claims in the GLP-1 litigation because vision loss is permanent and profoundly life-altering. Key evidence: ophthalmology records documenting NAION diagnosis, timeline showing diagnosis occurred during semaglutide use, and absence of other NAION risk factors.
Scientific Evidence
Risk of Non-Arteritic Anterior Ischemic Optic Neuropathy in Patients Prescribed Semaglutide
Hathaway JT, Shah MP, Hathaway DB, et al. (2024). JAMA Ophthalmology
Key Findings
- Type 2 diabetes patients: 8.9% NAION risk on semaglutide vs 1.8% on non-semaglutide medications
- Weight-loss patients: 6.7% NAION risk vs 0.8% on alternatives
- Risk was highest in first year of use
- Findings confirmed by Danish/Norwegian cohort study of 424,000+ patients
- EMA required European label update; Novo Nordisk has not updated U.S. labels
Risk of Gastrointestinal Adverse Events Associated With GLP-1 Receptor Agonists for Weight Loss
Sodhi M, Rezaeianzadeh R, Kezouh A, Bhatt M (2023). JAMA
Key Findings
- Gastroparesis hazard ratio: 3.67 (95% CI 1.15-11.90)
- Bowel obstruction hazard ratio: 4.22 (95% CI 1.02-17.40)
- Pancreatitis hazard ratio: 9.09 (95% CI 1.25-66.00)
- Study population was non-diabetic weight-loss patients — directly relevant to majority of MDL plaintiffs
- Findings were robust across sensitivity analyses
GLP-1 Receptor Agonists and Gallbladder Disease: A Systematic Review of Randomized Controlled Trials
Multiple authors (systematic review) (2024). Clinical Gastroenterology and Hepatology
Key Findings
- 37% increased relative risk of gallbladder disease across 76 RCTs
- Risk was more pronounced with higher doses and greater weight loss
- Rapid weight loss mechanism contributes to gallstone formation
- Risk increased with duration of GLP-1 agonist use
- Findings support inclusion of gallbladder disease in GLP-1 litigation claims
Related Pages
Ozempic Stomach Paralysis Lawsuit
Gastroparesis — stomach paralysis — is the primary injury in the GLP-1 MDL. Over 3,000 lawsuits allege that Ozempic and similar drugs cause a potentially permanent condition that was not adequately disclosed.
Ozempic Gallbladder Problems
GLP-1 drug users face a 37% increased risk of gallbladder disease. Rapid weight loss combined with GLP-1 effects on bile duct motility creates conditions for gallstone formation and cholecystitis.
Ozempic Pancreatitis Lawsuit
The JAMA 2023 study found a 9.09x increased risk of pancreatitis among GLP-1 users for weight loss. Acute pancreatitis can be life-threatening and requires hospitalization.
Ozempic Bowel Obstruction
GLP-1 drugs slow motility throughout the entire GI tract, not just the stomach. Severe slowing can cause ileus or mechanical bowel obstruction — life-threatening emergencies that may require surgery.
Ozempic Settlement Amounts
No GLP-1 trials have concluded yet, but projected settlements based on comparable pharmaceutical mass torts suggest $100,000 to $1.5 million+ depending on injury severity.
Novo Nordisk GLP-1 Lawsuit
Novo Nordisk generated $29.3 billion in semaglutide revenue in 2024 while allegedly failing to warn about severe side effects. The company's aggressive marketing and delayed label updates are central to the litigation.
Ozempic, Wegovy & Mounjaro Lawsuits
The GLP-1 MDL consolidates claims against both Novo Nordisk (Ozempic, Wegovy) and Eli Lilly (Mounjaro, Zepbound). All semaglutide and tirzepatide products are at issue.
Ozempic Vision Loss (NAION) Lawsuit
A growing body of evidence links GLP-1 receptor agonist medications — including Ozempic (semaglutide), Wegovy, and Mounjaro (tirzepatide) — to non-arteritic anterior ischemic optic neuropathy (NAION), a sudden loss of blood flow to the optic nerve that can cause permanent vision loss. A landmark Harvard/Mass Eye and Ear study published in 2024 found GLP-1 users face significantly elevated NAION risk. In December 2025, a second federal MDL was established specifically for NAION vision loss claims, separate from the existing gastroparesis MDL. As of late 2025, nearly 2,947 lawsuits have been filed by patients alleging vision damage. The first bellwether trials are scheduled for early 2026. If you experienced sudden vision loss, blurred vision, or were diagnosed with NAION while taking Ozempic, Wegovy, or Mounjaro, consult an attorney immediately.
Learn moreOzempic / GLP-1 Lawsuits Lawsuit
GLP-1 receptor agonist drugs — including Novo Nordisk's Ozempic, Wegovy, and Rybelsus, and Eli Lilly's Mounjaro and Zepbound — have generated over $40 billion in annual sales while allegedly causing severe gastrointestinal injuries that manufacturers failed to adequately disclose. Over 3,100 lawsuits are consolidated in MDL 3094 in the Eastern District of Pennsylvania, with a separate NAION vision-loss MDL (3163) established in December 2025.
View full case overview