In August 2024, a federal judge in Philadelphia counted 842 cases in consolidated litigation over GLP-1 drugs such as Ozempic, Wegovy and Mounjaro. Two years later, that number has passed 4,000. According to the U.S. Judicial Panel on Multidistrict Litigation’s November 2, 2026 report, the main gastrointestinal-injury docket, MDL 3094, holds 4,082 pending actions. A second federal docket involving a form of sudden vision loss, MDL 3163, has reached 278 cases, up from 247 on October 1.
That is roughly one additional vision-loss case per day over the last reporting interval. Together, the two federal proceedings contain 4,360 pending actions, excluding separate cases filed in state courts. No global settlement has been announced, and no bellwether trial schedule was confirmed in the publicly available court materials reviewed for this article.
For the manufacturers at the center of the obesity boom, the expanding GLP-1 lawsuit docket represents a legal challenge moving far more slowly than drug sales. For patients, it is a reminder that serious questions about drug warnings, individual injuries and scientific causation are being examined in court.
But there is a distinction that can disappear beneath a large headline number. A lawsuit counts an allegation. It is not proof that a drug caused an injury.
How the GLP-1 Lawsuit Docket Passed 4,000 Cases
The core federal litigation sits in the Eastern District of Pennsylvania before Judge Karen Spencer Marston. Plaintiffs allege that Novo Nordisk and Eli Lilly failed to provide adequate warnings about serious gastrointestinal injuries associated with their medicines, including gastroparesis, ileus and intestinal obstruction. The manufacturers deny the allegations.
Gastroparesis, a condition in which the stomach empties abnormally slowly, has been central to the lawsuits. GLP-1-based medicines can delay gastric emptying as part of their pharmacological action, but whether a particular treatment caused a persistent injury in an individual patient is a separate medical and legal question.
When BioSpace reported on Judge Marston’s early case-management order on August 30, 2024, there were 842 cases. Plaintiffs’ lawyers had already suggested the number could eventually reach thousands or even tens of thousands. The first part of that prediction has come true.
By November 2, 2026, the Judicial Panel on Multidistrict Litigation counted 4,082 actions pending in MDL 3094 and 4,196 total actions historically associated with it. Those are different measurements. The pending count includes open federal actions, while the historical total also reflects actions that are no longer pending in the proceeding.
The growth has not yet produced a comparable wave of courtroom verdicts. Multidistrict litigation often spends years addressing discovery, expert evidence and common legal questions before individual trials. Consolidation is primarily a mechanism for coordinated pretrial proceedings, not a judgment that thousands of plaintiffs have proved their claims.
Four thousand cases measure how many actions remain in court. They do not measure how many injuries have been legally established.
The Gastroparesis Ruling Has Already Narrowed the Legal Fight
The most consequential early decision in the gastrointestinal litigation has already been issued. In August 2024, Judge Marston agreed to prioritize common questions that could affect large groups of plaintiffs before proceeding to case-specific discovery and trials.
The first concerned diagnosis. Could a plaintiff reliably establish gastroparesis based on symptoms and clinical judgment alone, or was objective testing required? The answer mattered because symptoms such as nausea, vomiting and abdominal discomfort can occur for multiple reasons and do not, by themselves, establish a particular cause.
On August 15, 2025, Marston ruled that plaintiffs claiming gastroparesis must demonstrate a diagnosis supported by a properly performed gastric emptying study. The order identified gastric emptying scintigraphy, breath testing and wireless motility capsule testing as acceptable approaches.
That ruling established a significant evidentiary requirement. Plaintiffs who lack qualifying diagnostic evidence may face major obstacles in pursuing gastroparesis allegations. It did not, however, resolve every gastrointestinal claim or decide whether the medications caused specific injuries.
The next questions concern expert scientific testimony, general causation, federal preemption and the adequacy of product warnings. Marston held a Rule 702 evidentiary hearing in September 2026, with closing arguments on pending expert-evidence motions in October. As of the reporting reviewed here, those broader motions remained unresolved.
These decisions may prove more consequential than another thousand filings. Expert testimony must survive judicial scrutiny before juries can be asked to evaluate claims that depend on it. And if federal drug-labeling law preempts certain state-law warning claims, the available routes to liability may narrow further.
The litigation is no longer simply waiting to learn whether diagnosis requires objective evidence. The court has answered that question. The next battle is what the admissible science and labeling law permit plaintiffs to prove.
The Vision-Loss Docket Is Growing, but the Scientific Record Is Different
The second major federal proceeding concerns non-arteritic anterior ischemic optic neuropathy, or NAION. This uncommon disorder involves impaired blood supply to the optic nerve and can produce sudden, painless and sometimes permanent loss of vision.
Claims alleging NAION after treatment with GLP-1-based medicines have been consolidated in MDL 3163, also before Judge Marston. The federal docket contained 247 pending actions on October 1, 2026, and 278 on November 2, an increase of 31 cases over approximately one month.
New Jersey also has separate state-court proceedings. The state’s Supreme Court designated gastrointestinal and NAION cases as distinct multicounty litigations in October 2025, assigning centralized management to Bergen County. Those state cases are not included in the federal docket counts.
Grey Pepper previously covered the human allegations behind the vision-loss litigation in its report on Edward Gillen’s Ozempic lawsuit. The scientific evidence deserves equally careful attention, because this is not merely a legal theory unsupported by regulatory review.
In June 2025, the European Medicines Agency concluded that NAION is a very rare side effect of semaglutide, the active ingredient in Ozempic, Wegovy and Rybelsus. The agency recommended that product information reflect the risk, classifying its frequency as potentially affecting up to one in 10,000 people.
That is an important regulatory finding. It is also not the same as deciding the lawsuits. The EMA’s conclusion applies specifically to semaglutide and does not automatically establish the same risk across every GLP-1-related medicine. Nor does a recognized adverse reaction prove that any particular plaintiff’s vision loss was caused by a particular product, that a manufacturer’s warning was legally inadequate, or that damages are owed.
Those questions will depend on the medical histories, evidence, applicable law and warnings relevant to each case.
Gastroparesis claims have already faced a decisive diagnostic-evidence ruling. The NAION cases face their own combination of individual causation, labeling history and product-specific scientific questions. The legal battles overlap, but they are not interchangeable.
Compounders Are Facing a Different Kind of GLP-1 Lawsuit
The legal scrutiny is no longer limited to the manufacturers of branded medicines. On November 2, Law360 reported that a compounding pharmacy had been named in a proposed class action in New Jersey federal court, accused of misleading consumers in its marketing of compounded GLP-1 weight-loss medications.
According to the report, the complaint challenges representations that the compounded products were safe, effective, supported by clinical evidence and personalized to patients. The publicly accessible report did not provide sufficient complaint details to independently evaluate the allegations. They remain unproven.
This is a separate legal question from the product-liability MDLs. The federal gastrointestinal and NAION cases concern alleged personal injuries and responsibilities associated with the relevant medications. A consumer marketing suit examines what a seller represented about its products and whether those representations were legally permissible.
Compounding companies have also fought brand-name manufacturers over competition and access to the market. Grey Pepper covered one such dispute in its report on the dismissal of Strive’s antitrust case against Lilly and Novo. Consumer-protection allegations represent another potential source of litigation, but they should not be conflated with that antitrust dispute or the federal personal-injury totals.
What Will Determine Whether the GLP-1 Lawsuits Succeed?
Several decisions will determine whether the expanding docket becomes a substantial liability for drugmakers or narrows through expert-evidence rulings, dismissals and settlements.
The first is how Judge Marston resolves the remaining common questions in the gastrointestinal litigation, including general causation, expert admissibility and federal labeling defenses. The August 2025 diagnostic ruling showed that the court is willing to establish standards affecting large numbers of cases before individual trials.
The second is whether the NAION litigation develops an admissible, product-specific evidentiary record that supports individual claims. The EMA’s conclusion regarding semaglutide is relevant to the scientific discussion, but U.S. litigation must still address exposure, timing, alternative explanations, warning duties and the legal requirements of each claim.
The third is the progress of the separate New Jersey proceedings. Centralized state-court management may follow a different procedural calendar from the federal MDLs. It would be premature to predict that either venue will produce an earlier trial or a larger recovery.
Finally, the consumer litigation involving compounded medicines will test another issue: not simply whether a treatment caused an injury, but what evidence a seller needs before making claims about the safety, effectiveness and personalization of its products.
None of these proceedings means patients should independently discontinue prescribed medication. GLP-1-based drugs remain approved treatments for specified conditions, with benefits and risks evaluated through clinical trials and ongoing safety monitoring. Patients with concerns about adverse effects should discuss them with a healthcare professional. Sudden vision loss requires urgent medical assessment.
For now, the central distinction is unchanged. The litigation has accumulated more than 4,300 pending federal actions across two proceedings. What those cases will establish remains unresolved.
The obesity-drug market grew quickly. Its legal record is being built much more slowly, one filing, expert report and court order at a time.
Sources
- U.S. Judicial Panel on Multidistrict Litigation. Pending MDL Dockets by Actions Pending, November 2, 2026. Official federal case counts.
- U.S. District Court, Eastern District of Pennsylvania. MDL 3094 — GLP-1 Gastrointestinal Injury Litigation. Official proceedings and orders.
- U.S. District Court, Eastern District of Pennsylvania. Order on Gastroparesis Diagnostic Testing, August 15, 2025, MDL 3094, Document 468.
- U.S. District Court, Eastern District of Pennsylvania. MDL 3163 — NAION Products Liability Litigation. Official proceedings.
- European Medicines Agency. PRAC Concludes NAION Is a Very Rare Side Effect of Semaglutide Medicines, June 2025.
- New Jersey Courts. Designation of GLP-1 Gastrointestinal and NAION Vision-Loss Cases as Separate Multicounty Litigations, November 2025.
- BioSpace. Siding With Novo and Lilly, Court Agrees to First Tackle Cross-Cutting Issues, August 30, 2024.
- Law360. Pharmacy Hit With NJ Suit Over GLP-1 Marketing, November 2, 2026.
- Drugwatch. Ozempic Lawsuit: November 2026 Blindness and Gastroparesis Claims, updated November 4, 2026. Secondary litigation tracking.
