Sudden vision loss in one eye needs same-day care. Call an eye doctor or go to the emergency department.

Optic Nerve Health

GLP-1 receptor agonists and NAION: what prescribers should know

Reviewed by James Deom, OD, MPH, FAAO, Chief of Eye Care Services. Last reviewed: November 11, 2026.

Educational summary for clinicians. This is not a clinical practice guideline. Individualize care to each patient.

The short version

  • FDA, Nov 9, 2026: all GLP-1 RA labels (including tirzepatide and orforglipron) must add a potential increased risk of NAION to Warnings and Precautions.¹
  • Absolute risk is low. The FDA’s pooled analysis of 126 RCTs found 6.4 vs 3.8 NAION cases per 100,000 person-years (15 probable events in total).¹ A 2026 observational meta-analysis in T2D estimated about 1 excess case per 7,000 semaglutide-treated patients per year.²
  • Causation is not established. The signal is strongest for semaglutide. Confounding by indication (diabetes severity, OSA, hypertension) is a central problem, and the FDA found no mechanism in animal data.¹ ³
  • For most patients, the cardiometabolic, renal, and other benefits are likely to outweigh this small potential risk. The equation changes for patients with prior NAION or a known disc at risk.
  • Your most important actions: counsel patients on red-flag symptoms, ask about prior optic nerve disease, keep diabetic eye care current, and refer the same day for sudden monocular vision loss.

What NAION is

NAION is the most common acute optic neuropathy in adults over 50. It presents as sudden, painless, monocular vision loss, often noticed on waking, with a relative afferent pupillary defect, an altitudinal or arcuate field defect, and optic disc edema that becomes pallor over weeks.⁴ The main anatomic risk factor is a small, crowded optic disc (“disc at risk”). Optic disc drusen also predispose to it.⁴ There is no proven treatment, and having NAION in one eye raises the risk in the fellow eye.¹

Background incidence: 2.3–10.2 per 100,000 per year in adults over 50.¹ Systemic risk factors: age, male sex, hypertension, diabetes (especially with complications), OSA, hyperlipidemia, smoking, anemia, hypercoagulable states, nocturnal hypotension, and hypoperfusion events.⁵ ⁶

Where the evidence stands (November 2026)

Source Population / comparison Key finding
FDA trial meta-analysis (2026)¹ 126 RCTs, 134,253 patients 6.4 vs 3.8 per 100,000 PY; 15 probable events
FDA Sentinel (2026)¹ T2D, GLP-1 RA vs DPP-4i / SGLT-2i HR 1.43 (1.02–2.01) vs DPP-4i; HR 1.19 (0.91–1.54) vs SGLT-2i, not significant
Noh et al., Diabetes Care 2026⁷ UK T2D, GLP-1 RA vs DPP-4i 1-yr risk 18.5 vs 7.2 per 100,000; RR 2.56; RD 11.3 per 100,000; highest in first 6 months; higher with age <50, men, ever-smokers, A1c drop ≥1%
Ueda et al., Ann Intern Med 2026³ Sweden T2D, GLP-1 RA vs SGLT-2i 1-yr 0.04% vs 0.02% (RR 1.93); attenuated when restricted to metformin users, suggesting residual confounding
Chrzanowski et al., PLoS Med 2026² Meta-analysis, T2D, semaglutide HR 2.17; absolute 0.014% per year (about 1 in 7,000)
Hathaway et al., JAMA Ophthalmol 2024⁸ Neuro-ophthalmology referral cohort HR 4.28 (T2D), 7.64 (obesity). These are selected patients and the estimates are likely inflated.
Null or inconsistent studies⁹ ¹⁰ TriNetX cohorts; 2026 Ophthalmology meta-analysis No significant increase; pooled aHR 1.63 (0.88–2.39)

About individual agents: most data are for semaglutide. One study combining semaglutide and tirzepatide found HR 1.76 (1.01–3.07).¹¹ Agent-specific estimates for tirzepatide, dulaglutide, and others are limited. The FDA applied the warning class-wide because NAION has been reported with every marketed GLP-1 RA.¹

About obesity without diabetes: the evidence is thinner and less consistent than in T2D.¹⁰ ¹²

A fuller side-by-side table of positive, null, and mixed studies — and a discussion of where they agree and disagree — is on the study comparison page.

What professional groups advise

Official positions are not identical. They are summarized here and tabulated in more detail on the study comparison page.

Group Position (short version)
FDA (Nov 9, 2026)¹ Class-wide potential increased risk labeling. Instruct patients to report sudden vision changes immediately. Refer suspected NAION promptly. Consider discontinuing after NAION unless the benefits clearly outweigh the risk.
EMA / PRAC (June 2025; semaglutide)¹³ NAION is “very rare” (up to 1 in 10,000). Stop semaglutide if NAION is confirmed.
AAO & NANOS (2026)¹⁴ No routine exam solely to assess NAION risk. Continue diabetic eye exams. After NAION, use shared decision-making; they do not support blanket discontinuation. Discuss fellow-eye risk when there is prior NAION.
AOA (June 2025; public comment Nov 9, 2026)¹⁵ Comprehensive dilated exam within 12 months before starting, or a baseline exam within 1 month after. The June 2025 clinical report also states that if NAION is confirmed, GLP-1 RA treatment should be discontinued and the health care team consulted immediately. In a Nov 9, 2026 statement quoted in Optometry Times, the AOA said the FDA labeling change reinforces a baseline in-person comprehensive exam and appropriate follow-up, and that the rare risk should not cause unnecessary alarm.
AAO (diabetic retinopathy statement, Nov 2026)¹⁶a For patients with diabetes starting a GLP-1 RA, an initial period of increased diabetic-retinopathy monitoring is recommended, especially if baseline A1c has been poorly controlled. Evidence that GLP-1 RAs themselves worsen retinopathy is mixed and not conclusive; early worsening, if it occurs, may reflect rapid glycemic improvement. Shared decision-making with the care team.

Dr. Deom’s recommendation (clinical opinion / practice recommendation)

Dr. James Deom recommends that everyone starting or taking a GLP-1 medication have a comprehensive dilated eye exam with OCT, OCT angiography (OCTA), and retinal photography (fundus photos with autofluorescence) as a baseline and for follow-up, and seek same-day care for sudden vision loss.

This is his clinical opinion and practice recommendation, not a society mandate. He acknowledges that AAO and NANOS do not recommend routine exams solely to predict NAION, and that imaging does not reliably predict or prevent an acute event.

Why he recommends each test — for documentation, not for prediction:

  • OCT: a baseline measure of retinal nerve fiber layer (RNFL) and ganglion-cell layer (GCL) thickness, and of optic disc structure, to compare against if vision changes later.
  • OCT angiography (OCTA): a baseline record of peripapillary, optic nerve head, and macular perfusion.
  • Fundus photographs with autofluorescence: a baseline record of disc appearance, crowding, possible optic disc drusen, and retinal disease.

These tests do not reliably predict or prevent NAION. AAO and NANOS do not recommend a routine exam solely to predict NAION, and this site does not describe this imaging set as a NAION screening test. Dr. Deom still recommends it as a practice approach so that a baseline exists, other eye disease can be found, and disc anatomy is documented.

His practice approach is a baseline exam with this imaging set before starting or soon after (a practical window is within 12 months before or 1 month after, consistent with AOA timing), a repeat exam with the same imaging at a reasonable interval, and same-day evaluation for sudden vision loss. That is more proactive than the AAO/NANOS exam position. See the study comparison page and the monitoring framework.

Dr. James Deom’s personal clinical thought

This is his opinion, not established evidence. It is not a finding from the studies or a position of the FDA, EMA, AAO, NANOS, or AOA.

As patients lose weight and their overall health improves on GLP-1 medicines, blood pressure and cholesterol medicines are often not re-addressed. Over-treatment of blood pressure may lead to hypotension, which can worsen at night and could cause nighttime hypoperfusion of the optic nerve. That sequence would fit the typical presentation of NAION (vision loss noticed on waking).

He recommends that people on GLP-1 medicines also improve exercise and diet, and keep regular visits with their usual doctors, even if that clinician did not prescribe the GLP-1, so the rest of their care, including blood pressure, is maintained.

For prescribers: consider reviewing antihypertensive dosing and timing (including bedtime dosing) as weight drops. Coordinate changes with the patient’s usual clinician when someone else wrote the GLP-1 prescription.

A practical, suggested approach

This is a framework for discussion with your eye-care colleagues, not a validated protocol.

Before starting, ask three questions

  1. Have you ever had an optic nerve problem, sudden vision loss in one eye, or been told you have a “crowded” optic nerve or optic disc drusen?
  2. When was your last dilated eye exam? (Especially important with diabetes. Rapid A1c lowering can cause early worsening of diabetic retinopathy.)
  3. Do you snore, stop breathing in your sleep, or feel very tired during the day? (Consider OSA evaluation.)

Suggested baseline eye exam

  • Everyone: in line with Dr. Deom’s practice recommendation and AOA timing, urge a comprehensive dilated exam with OCT, OCT angiography (OCTA), and retinal photography (fundus photos with autofluorescence) within 12 months before starting or 1 month after, and plan a later visit with the same imaging at a reasonable interval. Patients with diabetes should also stay up to date on diabetic eye exams. These tests document a baseline; they have not been shown to predict or prevent NAION.
  • Prioritize a dilated exam with optic nerve assessment before starting (or very soon after) for patients with:
  • prior NAION or any optic neuropathy in either eye
  • known crowded disc, small cup-to-disc ratio, or optic disc drusen
  • moderate or severe nonproliferative or proliferative diabetic retinopathy, or long-standing poorly controlled diabetes where a large A1c drop is expected
  • retinal vein occlusion or a known hypercoagulable state
  • several vascular risk factors together (untreated OSA, smoking, hypertension with symptomatic or nocturnal hypotension, anemia)
  • In Dr. Deom’s practice recommendation, the baseline visit includes OCT (RNFL/GCL and disc structure), OCT angiography (peripapillary, optic nerve head, and macular perfusion), and fundus photographs with autofluorescence (disc appearance, crowding, possible disc drusen, and retinal disease). Visual fields may be added if the disc is abnormal, symptoms are present, or there is prior NAION. These tests document a baseline; they do not predict or prevent NAION.

During titration

  • Ask about new visual symptoms, dehydration (GI losses), and dizziness or orthostasis.
  • Watch for symptomatic or nocturnal hypotension as weight falls and antihypertensives continue. Review doses and timing when clinically indicated.
  • Coordinate with the eye doctor when A1c is falling rapidly in patients with retinopathy.

Counsel every patient (sample script)

“This medicine has a small possible link to a rare eye problem called NAION. It’s uncommon, and for most people the benefits are much larger. But if you ever notice sudden blurry, dim, or missing vision in one eye, especially when you wake up, call an eye doctor that same day and let me know. Please don’t stop the medicine on your own.”

When to refer

Situation Urgency
Sudden, painless vision loss or a new field defect in one eye Same day: ophthalmology/optometry or the ED. Contact the eye doctor directly.
Age over 50 with vision loss plus headache, jaw claudication, scalp tenderness, fever, or weight loss Emergency. Evaluate for giant cell arteritis (ESR, CRP, CBC with platelets). Do not delay treatment while waiting for an eye exam.
New headache with transient visual obscurations or pulsatile tinnitus, especially in a young patient with obesity (possible IIH/papilledema) Urgent eye exam (within days)
Prior NAION or known disc at risk before starting a GLP-1 RA Routine-soon. Coordinate the decision with eye care or neuro-ophthalmology.
Diabetes with no exam in the past 12 months, or known retinopathy, before a large A1c reduction Routine-soon
Asymptomatic patient with no eye risk factors Routine eye care per usual schedule

If NAION is diagnosed

  • Expect a call from the eye doctor. Decide together with the patient whether to continue, switch, or stop. The FDA says to consider discontinuation unless benefits clearly outweigh the risk,¹ and AAO/NANOS emphasize individualized shared decision-making.¹⁴
  • Weigh the fellow-eye risk against the patient’s cardiovascular, renal, metabolic, and OSA benefits, and consider alternative therapies.
  • Address modifiable factors: OSA, smoking, nocturnal hypotension, anemia, and lipids.
  • Report the case to FDA MedWatch.¹

Working with our team

Eye Specialists of NEPA welcomes co-management of patients starting or taking GLP-1 medicines. All five offices have OCT, OCT angiography, and fundus photography with autofluorescence. The offices offer priority scheduling for a baseline or follow-up exam with this imaging set.

Same-day evaluation: providers can call or text Dr. Deom’s cell at 570-436-1930.

General contact and referrals: Hazleton Eye Specialists, phone 570-453-2020, fax 570-453-1020.

  • Hazleton Eye Specialists: 281 Airport Road, Hazle Township, PA 18202 · 570-453-2020
  • Stroudsburg Eye Specialists: 2942 Route 611, Suite 5, Tannersville, PA 18372 · 570-421-3342
  • Nanticoke Eye Specialists: 233 S. Prospect St., Nanticoke, PA 18634 · 570-735-6000
  • Pottsville Eye Specialists: 541 West Bacon Street, Pottsville, PA 17901 · 570-628-3937
  • Bangor Eye Specialists: 385 Bangor Junction Rd., Bangor, PA 18013 · 610-588-0129

Office locations →

Medical disclaimer. This page is educational and is intended for licensed health care professionals. It is not a clinical practice guideline and does not replace clinical judgment, product labeling, or specialty consultation. Recommendations from regulators and professional societies differ and continue to evolve. Information is current as of the “last reviewed” date.

References

  1. U.S. FDA Drug Safety Communication, Nov 9, 2026. https://www.fda.gov/drugs/drug-safety-communications/fda-requires-safety-labeling-changes-glucagon-peptide-1-receptor-agonists-glp-1-ras-due-potential
  2. Chrzanowski J, et al. PLoS Med. 2026;23(5):e1005064. https://journals.plos.org/plosmedicine/article?id=10.1371/journal.pmed.1005064
  3. Ueda P, et al. Ann Intern Med. 2026;179(9):1232-1243. https://www.acpjournals.org/doi/10.7326/ANNALS-25-02096
  4. Biousse V, Newman NJ. Ischemic optic neuropathies. N Engl J Med. 2015;372:2428-2436.
  5. Cestari DM, et al. Ophthalmology. 2016. https://pubmed.ncbi.nlm.nih.gov/27659545/
  6. Liu B, et al. Front Med. 2021;8:618353. https://www.frontiersin.org/journals/medicine/articles/10.3389/fmed.2021.618353/full
  7. Noh Y, et al. Diabetes Care. 2026;49(5):763-771. https://diabetesjournals.org/care/article/49/5/763/164499/
  8. Hathaway JT, et al. JAMA Ophthalmol. 2024;142(8):732-739. https://jamanetwork.com/journals/jamaophthalmology/fullarticle/2820255
  9. TriNetX matched cohort. Am J Ophthalmol. 2025. https://www.ajo.com/article/S0002-9394(25)00094-7/fulltext
  10. Semaglutide and the risk of NAION: meta-analysis. Ophthalmology. 2026. https://www.aaojournal.org/article/S0161-6420(26)00082-5/fulltext
  11. Semaglutide or tirzepatide and optic nerve disorders in T2D. JAMA Netw Open. 2025. https://jamanetwork.com/journals/jamanetworkopen/fullarticle/2837377
  12. Dhivagaran T, et al. Neurology. 2026;106(10):e214864. https://www.neurology.org/doi/10.1212/WNL.0000000000214864
  13. EMA PRAC, Jun 6, 2025. https://www.ema.europa.eu/en/news/prac-concludes-eye-condition-naion-very-rare-side-effect-semaglutide-medicines-ozempic-rybelsus-wegovy
  14. AAO & NANOS consensus statement (May 2026): https://www.aao.org/education/clinical-statement/glucagon-like-peptide-1-receptor-agonists-risk-of- · News release, Sep 22, 2026: https://www.aao.org/newsroom/news-releases/detail/what-data-say-about-glp-1-drugs-vision-loss
  15. AOA clinical report, June 2025. https://www.aoa.org/AOA/Documents/Practice%20Management/Clinical%20Guidelines/AOA%20GLP-1_EBO_clinical-report.pdf · Nov 9, 2026 AOA comment as quoted in Optometry Times: https://www.optometrytimes.com/view/fda-now-requiring-naion-warning-across-glp-1-receptor-agonist-class (official AOA statement URL not independently opened) 16a. American Academy of Ophthalmology. GLP-1 receptor agonists and diabetic retinopathy: a statement from the American Academy of Ophthalmology. November 2026. https://www.aao.org/education/clinical-statement/glucagon-like-peptide-1-receptor-agonists-diabetic