Dozens of lawsuits have emerged against manufacturers of GLP-1 drugs as patients claim they were not adequately warned about the potential risk of a rare vision loss condition associated with these medications.
In recent developments, a growing number of lawsuits have been filed against the manufacturers of GLP-1 receptor agonist medications, including semaglutide, as plaintiffs allege that they were not properly informed about the risk of non-arteritic anterior ischemic optic neuropathy (NAION), a rare condition characterized by sudden, painless vision loss in one eye. This condition occurs when the optic nerve experiences insufficient blood flow, leading to significant visual impairment.
The American Academy of Ophthalmology (AAO) and the North American Neuro-Ophthalmology Society (NANOS) have taken steps to address these concerns by evaluating existing research on the relationship between GLP-1 drugs and NAION. In May 2026, these organizations published their findings in the most extensive review of data to date, analyzing over 40 studies related to this potential side effect.
Findings on Risk and Incidence
The review identified that the use of semaglutide, one specific GLP-1 receptor agonist, may be associated with approximately a two-fold increase in the relative risk of developing NAION. However, it is essential to note that NAION remains a rare condition, affecting between 2.3 and 10.2 individuals per 100,000 annually. This doubling of risk translates to only a minimal increase in the absolute number of cases, suggesting that while there may be an increased relative risk, the actual incidence remains low.
Despite the identified risk, the evidence surrounding this potential side effect is mixed. Larger studies tend to yield a higher likelihood of detecting risk; however, reliance on diagnosis codes that have not been confirmed by specialized neuro-ophthalmologists may lead to imprecision in findings. Notably, some large-scale analyses, including a comprehensive study involving 1.2 million patients from the Military Health System, found no increased risk of NAION associated with the use of semaglutide.
Causation and Medical Recommendations
As of now, no definitive causal relationship between GLP-1 medications and NAION has been established. Moreover, laboratory research has indicated that GLP-1 activity might serve to protect nerve tissue rather than contribute to its damage. In light of these findings, the European Medicines Agency (EMA) previously recommended labeling GLP-1 drugs with NAION as a ‘very rare’ side effect and advised discontinuation of semaglutide in confirmed cases of NAION.
In contrast, the AAO and NANOS have advised that a blanket recommendation to stop semaglutide for all patients may not be appropriate. They emphasize the importance of considering the overall health and risk factors of patients, particularly those with severe obesity, poorly controlled diabetes, or cardiovascular disease, for whom halting the medication could pose greater risks than the rare occurrence of an eye-related event.
The organizations recommend a shared decision-making process between patients and healthcare providers, including specialists such as ophthalmologists, neuro-ophthalmologists, neurologists, and primary care physicians. This collaborative approach aims to assess individual health profiles, risk factors, and available therapeutic options, enabling patients to make informed decisions regarding the continuation or cessation of semaglutide.
Routine Assessments and Patient Guidance
Furthermore, the AAO and NANOS do not endorse the practice of conducting routine eye exams solely to evaluate the risk of NAION prior to initiating GLP-1 medications. They emphasize that individuals with diabetes should continue their regularly scheduled diabetic eye exams, and patients who have previously experienced NAION in one eye do not require additional screenings, as their risk status is already established. However, these patients are encouraged to discuss the risk to their other eye with their healthcare providers prior to starting GLP-1 therapy.
Dr. Larry Frohman, executive vice president of NANOS, stated, “There are established risk factors for NAION. While we research whether GLP-1 medications may play a role in increasing the risk of NAION, we encourage patients with other potential risk factors to work with their physicians to try to minimize all of their risks where possible.”
Dr. Raj Maturi, a clinical spokesperson for the AAO, added, “People with diabetes are known to be at higher risk to develop NAION regardless of medication use, so more research is necessary to confirm what role semaglutide medications have in this occurrence, if at all.” He further highlighted other recognized risk factors for NAION, including untreated sleep apnea and overnight low blood pressure, reinforcing the need for comprehensive patient education and discussion about risks before starting treatment.
About the Organizations
The American Academy of Ophthalmology is the largest global association of eye physicians and surgeons, comprising a community of 32,000 medical doctors dedicated to preserving sight and enhancing lives through education, advocacy, and research. The North American Neuro-Ophthalmology Society consists of approximately 700 members specializing in neuro-ophthalmic diseases, committed to promoting equitable education, research, and clinical practice in this field.
