title: A case of nonarteritic ischemic optic neuropathy (NAION) in a male patient taking sildenafil.
abstract: Sildenafil is a phosphodiesterase-type-5 inhibitor indicated for the treatment of erectile dysfunction in men. We report a case of NAION identified from a cohort of 8,893 patients (from a Prescription-Event Monitoring study) prescribed sildenafil by their primary care physician in England between April and June 1999. This 61-year-old patient had risk factors for NAION independent of drug therapy. It was not possible to be confident about a causal association between sildenafil and NAION, though the possibility could not be ruled out. Epidemiological data suggest that one case of NAION might be expected in a cohort of 8,893 subjects. Thus it remains important for clinicians to consider the range of risk factors for NAION; while equally, the processes of pharmacovigilance need to continue as for any recently launched drug preparation.
mesh_terms: D006801:Humans; D008297:Male; D008875:Middle Aged; D018917:Optic Neuropathy, Ischemic / Q000139:chemically induced* / Q000503:physiopathology; D010879:Piperazines / Q000009:adverse effects*; D011358:Product Surveillance, Postmarketing; D011687:Purines; D000068677:Sildenafil Citrate; D013450:Sulfones
chemical_list: D010879:Piperazines; D011687:Purines; D013450:Sulfones; D000068677:Sildenafil Citrate