FAERS analysis finds a probable tirzepatide optic neuropathy signal

A study published in Hospital Pharmacy looked at reports filed with the FDA Adverse Event Reporting System (FAERS) between January 2022 and June 2025 and found 28 cases of ischemic optic neuropathy in which tirzepatide was listed as the primary suspect drug ^[1]. Tirzepatide is the active ingredient in Mounjaro and Zepbound. The condition involves reduced blood flow to the optic nerve and can cause sudden vision loss.

Using a database tool called OpenVigil 2.1, the researchers calculated a reporting odds ratio of 2.599, meaning these eye events were reported disproportionately more often with tirzepatide than with other drugs in the same database ^[1]. Two related statistical measures, the proportional reporting ratio (2.598) and relative reporting ratio (2.522), pointed in the same direction ^[1]. Based on a scoring system called Evans criteria, the authors classified the association as "probable" ^[1]. The confidence intervals for all three measures stayed above 1, which the authors say supports a real signal rather than random noise ^[1].

The researchers paired this with a separate look at Google Trends data from 2020 to 2025, which showed a sharp, exponential rise in global search interest for tirzepatide, especially in Western countries with high rates of obesity and type 2 diabetes ^[1]. They raised this pattern themselves as a caveat: as more people search for and take a drug, more side effects of any kind tend to get reported for it, whether or not the drug is actually causing more harm ^[1]. This is a known limitation of spontaneous reporting systems like FAERS, where reports come from patients, doctors, and pharmacists rather than from controlled studies, and rising public attention can inflate reporting rates on its own ^[1].

This is not the first paper to raise concerns about GLP-1 drugs and eye problems. A 2025 study in the American Journal of Ophthalmology looked at optic nerve and retinal adverse events tied to GLP-1 receptor agonists across 180 countries ^[1]. Separately, a 2025 JAMA Ophthalmology paper examined ophthalmic complications linked to both semaglutide and tirzepatide ^[1]. The new FAERS analysis adds a specific, calculated signal for tirzepatide and ischemic optic neuropathy using standard pharmacovigilance methods ^[1].

Why it matters for patients

The authors describe the event as "rare but serious" ^[1]. A reporting odds ratio above 1 with Evans criteria meeting "probable" status means the FAERS data show more optic neuropathy reports tied to tirzepatide than would be expected if there were no link, but it does not establish how common the condition actually is among people taking the drug, nor does it prove tirzepatide causes it ^[1]. FAERS reports are not verified for accuracy and do not include a comparison group of people who did not take the drug, so the database cannot show the real-world rate of this side effect or rule out other causes ^[1].

The authors themselves flag the Google Trends pattern as a reporting-bias caveat, not a confirmation of harm ^[1]. In plain terms, more prescriptions and more public attention to a drug can lead to more reports of any side effect, including ones the drug did not cause. The study's authors call for further investigation and say clinicians should give the finding "cautious clinical consideration," without spelling out what that should look like in practice ^[1].

What happens next

The paper does not describe a follow-up study, a regulatory review, or a labeling change tied to this signal ^[1]. The authors say integrating pharmacovigilance data with tools like Google Trends may help with early detection of rare drug reactions going forward, but they do not give a timeline for additional research on tirzepatide and ischemic optic neuropathy ^[1]. Whether the FDA or drug manufacturers respond with formal safety communications is not addressed in the available sources.