A 58-year-old man with symptomatic erythropoietic protoporphyria (EPP) noted that he was no longer photosensitive while undergoing long-term warfarin therapy associated with aortic valve replacement. His loss of photosensitivity occurred despite habitual intense sun exposure. In preparation for elective arthrodesis of his toe, he discontinued warfarin treatment, and within 48 hours his sun sensitivity recurred and worsened over the days before surgery. When warfarin treatment was resumed, without any other medication changes, his photosensitivity ceased despite the intense sunlight of the Australian summer, suggesting an antioxidant and anti-inflammatory effect of warfarin in mitigating the symptoms of porphyria.
Winship I, Ross G, Nicoll A, Hogan C, Leong Y, Varigos G. Antioxidant Effect of Warfarin Therapy: A Possible Symptomatic Treatment for Erythropoietic Protoporphyria. Arch Dermatol. 2009;145(8):960-961. doi:10.1001/archdermatol.2009.165