NAION (non-arteritic anterior ischemic optic neuropathy) has been reported in association with which medication?

• A. Latanoprost
• B. Acetazolamide
• C. Prednisone
• D. Sildenafil

Answer: (D)

NAION happens when the front part of the optic nerve doesn’t get enough blood, especially in people with vascular risk factors. Some medications have been watched for possible links to this ischemic event. Among the drugs listed, sildenafil has been reported in case reports and postmarketing data to be associated with NAION. The idea is that sildenafil, a PDE5 inhibitor, can affect systemic and ocular blood flow or perfusion pressure around the optic nerve head. In susceptible individuals, these changes may contribute to ischemia of the optic nerve.

Other drugs listed are not recognized as NAION triggers. Latanoprost is a glaucoma drop with mainly local eye surface effects. Acetazolamide can cause systemic metabolic effects but isn’t a known precipitant of NAION. Prednisone is a systemic steroid used for inflammatory optic conditions but is not linked as a cause of NAION, and evidence does not support it preventing or treating NAION.