13/03/2026
Semaglutide & Vision 👀 Risk - what does the evidence actually show?
👁 NAION (non-arteritic anterior ischaemic optic neuropathy) is a rare condition caused by reduced blood flow to the optic nerve.
📊 It affects about 2–10 people per 100,000 each year (roughly 1 in 10,000–50,000 people).
Risk is already higher in people with:
- diabetes
- high blood pressure
- sleep apnoea
- cardiovascular disease
- smoking history
- certain optic nerve anatomy
🧾 A new study in the British Journal of Ophthalmology analysed 30+ million adverse-event reports submitted to the US FDA.
The researchers found NAION reports appeared more often in people taking semaglutide medicines. But this does NOT mean the true risk is 17× higher.
Pharmacovigilance databases:
• rely on voluntary reports
• can be influenced by reporting bias and media attention
• cannot calculate the true incidence
• cannot fully adjust for underlying health risks
They are useful because they can detect early safety signals for rare events.
Other studies have shown mixed results.
Some suggest a small relative increase, but the absolute risk remains very low.
Regulators estimate the possible medication-related risk at around 1 in 10,000 people.
➡️ Key takeaway
There is enough emerging evidence to raise awareness and continue monitoring.
But there is not enough evidence to conclude that semaglutide directly causes NAION.
As always, treatment decisions should balance potential risks with the well-established benefits of treating obesity and metabolic disease.
🔗 Study discussed: https://bjo.bmj.com/content/early/2026/03/02/bjo-2025-328483
