Clinical Guide: Managing GLP-1 Ocular Manifestations and NAION Risks in Optometric Practice

Podcast: Play in new window | Download | Embed

Subscribe: Apple Podcasts | Spotify | Amazon Music | Android | RSS

The rapid increase in the use of GLP-1 receptor agonists (GLP-1RAs), such as semaglutide (Ozempic, Wegovy) and tirzepatide (Mounjaro, Zepbound), has significantly changed the landscape of co-management in healthcare. Currently, about 6% of adults in the U.S. are prescribed these medications. As a result, the American Optometric Association (AOA) has classified these patients as “at-risk,” indicating that they require specialized clinical oversight.

In Partnership with The American Optometric Association

Expert Insight: Dr. Andrew Morgenstern on Systemic Reach

Dr. Andrew Morgenstern, Director of the AOA Clinical Resources Group, emphasizes that GLP-1 receptors are not localized solely to the gastrointestinal tract. They are expressed throughout the central nervous system and the cardiovascular system, meaning their impact is truly systemic. According to Dr. Morgenstern, the “magical” efficacy of these drugs in dropping blood sugar and weight requires optometrists to look beyond the gut and focus on how rapid metabolic shifts influence ocular physiology.

Pathophysiology of GLP-1 Ocular Manifestations

Based on the AOA EBO Committee’s findings and Dr. Morgenstern’s clinical analysis, the primary ocular concerns for patients on GLP-1RAs include:

• The “Early Worsening” Paradox: Rapid glycemic optimization (a sudden drop in HbA1c) can paradoxically exacerbate preexisting diabetic retinopathy. Clinical data, specifically from the SUSTAIN-6 trial, confirms this transient but significant risk during the initial months of therapy.
• Refractive Shifts: The swift drop in blood glucose causes osmotic shifts within the lens. This manifests as acute blurred vision as the eye’s refractive power changes faster than the patient can adapt.
• Vasospasms and Headaches: Dr. Morgenstern notes that GLP-1s can cause vasospasms, which may manifest as headaches and are suspected to contribute to the development of NAION. These are vascular events, not lens-based ones.
• Neovascular AMD Concerns: The AOA clinical report highlights emerging 2025 research suggesting a potential association between GLP-1 use and an increased relative risk of developing neovascular Age-Related Macular Degeneration (AMD).

Assessing NAION and the “Disc at Risk”

A major focus of current clinical monitoring is the rare but serious risk of NAION (Non-arteritic Anterior Ischemic Optic Neuropathy).

• The Anatomical Red Flag: Dr. Morgenstern stresses the vital importance of identifying a “disc at risk”—a small cup-to-disc ratio with a crowded optic nerve head—during a baseline exam. Patients with this specific anatomy may be at a higher relative risk for an “eye stroke” when initiating semaglutide therapy.
• Regulatory Updates: In June 2025, the EMA officially categorized NAION as a “very rare” side effect of semaglutide, occurring in approximately 1 in 10,000 patients.

Sarcopenia and Fall Risks in the Senior Population

For patients over 65, the AOA report warns of sarcopenia, or the rapid loss of lean muscle mass that can accompany GLP-1 use. Dr. Morgenstern highlights a critical safety concern: when this physical weakness is paired with visual impairment from glaucoma or AMD, the risk of life-threatening falls increases exponentially.

AOA Clinical Protocol: The New Standard of Care

Per the AOA Evidence-Based Optometry Committee, the following is the recommended standard of care for all GLP-1 users:

1. Mandatory Baseline Exam: A comprehensive, dilated eye examination must be performed within 12 months prior to starting a GLP-1RA or within one month of initiation.
2. Screening for Retinopathy and Disc Structure: Practitioners must specifically document preexisting retinopathy levels and identify any “disc at risk” anatomy.
3. High-Frequency Monitoring: Patients with poorly controlled diabetes at the start of therapy require closer follow-up (every 3–6 months) during the first 12–18 months of treatment.
4. Interdisciplinary Collaboration: Optometrists should maintain an open line of communication with prescribing physicians regarding any visual changes or increased physical frailty.

Clinical Conclusion

The goal of the AOA and experts like Dr. Morgenstern is not to discourage the use of these transformative medications, but to ensure “informed monitoring.” By serving as the primary guardians of ocular health, optometrists play a vital role in the interdisciplinary team, helping patients achieve systemic health while mitigating sight-threatening risks.