Safety Alert: Semaglutide and Non-arteritic Anterior Ischemic Optic Neuropathy
The MHRA has issued a safety update regarding a very rare but serious risk associated with semaglutide-containing medicines. Clinicians and responders should be aware of this potential adverse effect, particularly when counselling patients or assessing vision-related complaints.
What is NAION?
Non-arteritic anterior ischemic optic neuropathy (NAION) is a condition characterised by sudden vision deterioration, typically affecting one eye. It results from reduced blood flow to the optic nerve and can occur with little warning.
Key Points
- NAION has been very rarely reported in patients taking semaglutide
- Patients may present with sudden vision loss or blurred vision in one eye
- The condition requires urgent ophthalmological assessment
- Risk factors for NAION include age, hypertension, and diabetes
Affected Medicines
This alert applies to all semaglutide-containing products:
- Wegovy (weight management)
- Ozempic (type 2 diabetes)
- Rybelsus (type 2 diabetes)
Recommended Actions
- Advise patients to seek immediate medical attention if they experience sudden vision loss or changes in vision
- Consider NAION in the differential diagnosis of acute vision loss in semaglutide users
- Review patient risk factors at each consultation
- Document any vision-related concerns in patient records
Further Information
For the full MHRA safety update, visit the MHRA Drug Safety Update page.