A 50-year-old man with a history of protein S deficiency treated by long-term warfarin presented with right non-arteritic optic neuropathy. Following successful augmentation of warfarin to minimise the effect of thrombophilia, he had a recurrence in the right eye and involvement of the left eye 11 days after the initial onset. Further investigation showed a marginal blood lipid profile, which was treated with lipid-lowering agents. A combination of aetiologies was seen in this patient. Other unique factors, such as the short duration to recurrence and involvement of the fellow eye, are discussed.