Weight & Metabolic Health

The GLP-1 eye-injury lawsuits: what MDL 3163 actually is

By the US Health Digest editorial team · Published August 18, 2026 · Every claim linked to its primary source

Federal lawsuits alleging that GLP-1 drugs caused a rare optic-nerve injury called NAION were gathered into one docket — MDL No. 3163 — by the Judicial Panel on Multidistrict Litigation on December 15, 2025, before U.S. District Judge Karen S. Marston in the Eastern District of Pennsylvania; the Panel's statistics report dated August 3, 2026 lists 200 actions pending. An MDL is a consolidation for pretrial proceedings under 28 U.S.C. §1407 — not a class action, and not a ruling that anything caused anyone's injury. Every claim in those cases is an allegation contained in court filings, and US Health Digest takes no position on the merits. This is not legal or medical advice, and nobody should stop a prescribed medicine because of a lawsuit; that is a conversation with a prescriber.

What actually happened, in the court's own words

The Judicial Panel on Multidistrict Litigation is a body of seven federal judges that decides only where related federal cases are heard. On December 15, 2025 it created a new docket, "IN RE: Glucagon-like Peptide-1 Receptor Agonists (GLP-1 RAs) Non-Arteritic Anterior Ischemic Optic Neuropathy Products Liability Litigation," MDL No. 3163, then covering what the Panel described as "21 actions pending in three districts" — of which it centralized 20, denying the motion as to one — plus nine related actions. Notably, the motion came from the defence side: "Defendant Eli Lilly and Company moves under 28 U.S.C. §1407 to centralize this litigation in the Eastern District of Pennsylvania", with Novo Nordisk A/S and Novo Nordisk Inc., also defendants, backing that district while plaintiffs preferred New Jersey. Those companies are named here only as parties identified in the court's records.

The order states the claims as claims. "Plaintiffs allege that their use of Eli Lilly's or Novo Nordisk's GLP-1 RA drugs (specifically, Ozempic, Wegovy, Saxenda, and Trulicity) caused them to suffer from non-arteritic anterior ischemic optic neuropathy (NAION)," the Panel wrote, identifying the shared factual questions as those "concerning the development, manufacture, testing, regulatory history, promotion, and labeling of the products, as well as their capacity to cause NAION." Plaintiffs "bring substantially identical claims for failure to warn, design defect, and breach of warranties" — the same three theories listed on the Eastern District of Pennsylvania's own page for the case.

None of that is a finding. A transfer order decides venue and case management. It does not weigh evidence, and the Panel said nothing about whether these drugs cause NAION.

What an MDL is — and four things it is not

Multidistrict litigation exists because one product can generate hundreds of near-identical federal suits in dozens of districts. The statute, 28 U.S.C. §1407(a), is essentially one sentence: "When civil actions involving one or more common questions of fact are pending in different districts, such actions may be transferred to any district for coordinated or consolidated pretrial proceedings." The Panel says its job is to decide whether cases share such questions and to select the judge, in order "to avoid duplication of discovery, to prevent inconsistent pretrial rulings, and to conserve the resources of the parties, their counsel and the judiciary."

• It is not a class action. In a class action, one representative case binds a group. In an MDL each lawsuit stays its own case, with its own plaintiff, facts and outcome.
• It is not a trial. The transfer is expressly for pretrial proceedings. The Panel's order names "preemption, expert admissibility, and other issues" as the things it wanted decided consistently in one court.
• It is not permanent. Per the Panel, "transferred actions not terminated in the transferee district are remanded to their originating transferor districts" at or before the end of centralized pretrial proceedings — unresolved cases go home for trial.
• It is not a verdict, a settlement or a recall. A case count counts filings: MDL 3163 went from 20 centralized actions at its creation to 200 pending as of the JPML's August 3, 2026 report — about eight months — per the JPML's own reports — a measure of litigation activity, not of causation.

Two GLP-1 MDLs, one judge, different injuries

This is the point most headlines blur. Two GLP-1 multidistrict dockets sit before the same judge in the same courthouse, and they concern different alleged harms. The older one, MDL No. 3094, is the gastrointestinal litigation; the Eastern District of Pennsylvania labels its page for it "(GI Injuries)" and quotes the finding that those actions share common issues of fact regarding "whether defendants knew or should have known that their GLP-1 RA products can cause gastroparesis and other gastrointestinal injuries." The same court page records that the Novo Nordisk defendants and Eli Lilly and Company deny those allegations. The 2025 transfer order creating the NAION docket draws the line itself: "Although the injury alleged here is different from the gastrointestinal injuries at issue in MDL No. 3094, there will be substantial overlap between pretrial proceedings in these litigations."

The Panel gave the new docket to Judge Marston because she already had the GI cases, the same defendants and largely the same counsel appear in both, and some plaintiffs allege both injuries. But it declined Eli Lilly's request to fold the NAION cases into MDL 3094, reasoning that a separate docket "will allow Judge Marston to determine the appropriate level of coordination between the litigations, make tracking of cases easier, and facilitate orderly docketing in each MDL." The line is policed: one case, Garcia, was excluded from the NAION docket after the plaintiff amended his complaint to drop the vision allegations and plead only gastrointestinal injuries.

What NAION is

Non-arteritic anterior ischemic optic neuropathy is a stroke-like event at the front of the optic nerve. The NIH-hosted StatPearls review describes the classic presentation as sudden, painless, one-eyed vision loss noticed on waking, in adults over about 50, caused by reduced blood flow in the small arteries supplying the optic nerve head; the resulting swelling inside a tight scleral canal compresses the nerve fibers. Its known risk factors are vascular: hypertension, high cholesterol, diabetes, cardiovascular and cerebrovascular disease, obstructive sleep apnea — the same conditions that lead people to a GLP-1 prescription, which is precisely why untangling drug from patient is hard. The damage is usually permanent and there is no established treatment, which is why a rare risk is still worth taking seriously.

The science, kept separate from the lawsuit

Litigation and evidence move on different clocks, and a filing count is not data. Our full review of the clinical evidence — the 2024 single-center study, the 2026 meta-analysis and the absolute risk in plain numbers — is in semaglutide and sudden vision loss. Where regulators stand:

The largest US cohort study we identified is a target-trial emulation in JAMA Ophthalmology (March 2026) following veterans with type 2 diabetes who started semaglutide versus an SGLT2 inhibitor. NAION incidence was 123 per 100,000 person-years among semaglutide initiators versus 67 per 100,000 among the comparator group — a hazard ratio of 2.33 (95% CI, 1.54–3.54), which the authors summarised as a "rare but evident increased risk." Two limits carry it: this is an observational hazard ratio from a new-user, active-comparator design, not a randomized-trial estimate; and the cohort was 85.5% male, in a drug class whose pivotal weight-loss trials were roughly three-quarters female — so it does not directly measure risk in women taking semaglutide for weight loss.

What the US label says today

We checked this ourselves rather than repeating it. Searching the current Structured Product Labels on DailyMed — the National Library of Medicine's canonical source for US prescribing information — for "NAION," "nonarteritic," "non-arteritic" and "ischemic optic neuropathy" returned zero matches in any of five current labels — the four products named in the MDL 3163 transfer order, plus the oral semaglutide label, which that order does not name: Ozempic (SPL v20, revised June 2026), Wegovy (v19, revised 06/2026), Saxenda (v22, SPL effective February 25, 2026) and Trulicity (v62, published August 10, 2026) — plus Rybelsus / oral semaglutide (v13, revised 1/2026). So: as of August 18, 2026, on the evidence of those five DailyMed records, US prescribing information for these products does not list NAION. That is a statement about what those documents contained on that date, and nothing more. A vision change you suspect may be drug-related can be reported to FDA's MedWatch program, which accepts reports from patients as well as clinicians.

What a patient should actually do with this

1. Sudden vision loss in one eye is an emergency regardless of cause. NAION, retinal artery occlusion, retinal detachment and giant cell arteritis can all present that way, and several are time-critical. Do not wait to see whether it clears — contact a clinician or eye service the same day.
2. Do not stop a prescribed medicine because of a lawsuit or an advertisement. EMA's advice is to stop semaglutide only if NAION is confirmed. Stopping a diabetes or obesity medicine on your own has its own consequences, covered in our guide to GLP-1 side effects.
3. Keep the absolute numbers in view. Even in the studies that found an association, events are counted in cases per 100,000 person-years. A doubled relative risk applied to a very rare condition leaves a very rare condition. That is not a reason to dismiss it — NAION's permanence is why regulators acted — but it is the right scale for a decision that also weighs what the medicine is doing for you.

We are a health publication, not a law firm. If you believe you have been injured, that is a question for a licensed attorney of your own choosing. Nothing here is legal advice.

Questions for your prescriber

• Do I have the vascular risk factors associated with NAION — hypertension, high cholesterol, diabetes, cardiovascular disease, sleep apnea — and does that change your view of this drug for me?
• The EMA, the UK MHRA and Australia's TGA have all acted on NAION — the TGA has added it to Australian Product Information, while the EMA and MHRA have directed that product information be updated — and the current US labels we checked have not — how are you weighing that?
• Should I have a baseline eye exam before or during treatment, given my history?
• What should I do, and whom should I call, if I wake up with vision loss in one eye?
• If I have had NAION in one eye already, does that change anything about this prescription?

More in our GLP-1 FAQ hub and our comparison of the two leading injectables.

Sources

1. United States Judicial Panel on Multidistrict Litigation. Transfer Order, MDL No. 3163, In re: Glucagon-like Peptide-1 Receptor Agonists (GLP-1 RAs) Non-Arteritic Anterior Ischemic Optic Neuropathy Products Liability Litigation, filed December 15, 2025 (Document 49). Transfer order (PDF).
2. JPML. MDL Statistics Report — Distribution of Pending MDL Dockets by Actions Pending, report date August 3, 2026 (MDL 3094: 3,928 pending / 3,962 historical; MDL 3163: 200 / 200). Pending MDLs index; report (PDF).
3. JPML. MDL Statistics Report — Docket Summary Listing by MDL Number, report date August 3, 2026 (judge, district, docket numbers, filing and transfer dates). Report (PDF).
4. JPML. About the Panel — statutory role, purposes of centralization, and remand of transferred actions. jpml.uscourts.gov/about-panel.
5. 28 U.S.C. §1407, Multidistrict litigation. United States Code via GovInfo.
6. U.S. District Court for the Eastern District of Pennsylvania. MDL 3163 court information page. paed.uscourts.gov — MDL 3163.
7. U.S. District Court for the Eastern District of Pennsylvania. MDL 3094 court information page ("GI Injuries"). paed.uscourts.gov — MDL 3094.
8. Kaur K, Margolin E. Nonarteritic Anterior Ischemic Optic Neuropathy. StatPearls [Internet]. StatPearls Publishing; last update September 14, 2025. NCBI Bookshelf NBK559045.
9. European Medicines Agency. PRAC concludes eye condition NAION is a very rare side effect of semaglutide medicines Ozempic, Rybelsus and Wegovy. June 6, 2025. ema.europa.eu.
10. Medicines and Healthcare products Regulatory Agency (UK). Drug Safety Update: Semaglutide and non-arteritic anterior ischaemic optic neuropathy (NAION). February 5, 2026. MHRA Drug Safety Update (PDF).
11. Therapeutic Goods Administration (Australia). GLP-1 RAs and rare vision disorder — Medicine Safety Update. July 23, 2026. tga.gov.au.
12. Heberer K, Bress AP, Cogill S, Maldonado AI, et al. New-Onset Nonarteritic Anterior Ischemic Optic Neuropathy and Initiators of Semaglutide in US Veterans With Type 2 Diabetes. JAMA Ophthalmology. 2026 Mar 1;144(3):259–264. PubMed 41678180. Erratum: JAMA Ophthalmol. 2026 Jun 1;144(6):571 (Figure 2; none of the figures cited here come from Figure 2).
13. DailyMed (US National Library of Medicine), current Structured Product Labels checked August 18, 2026: Ozempic, Wegovy, Rybelsus / oral semaglutide, Saxenda, Trulicity.
14. US Food and Drug Administration. MedWatch: The FDA Safety Information and Adverse Event Reporting Program. fda.gov/safety/medwatch.