Celecoxib Erythema multiforme-type drug eruption in an elderly patient: case reportA 79-year-old woman developed an erythema multiforme-type drug eruption while receiving celecoxib for stage IV squamous cell lung cancer.The woman presented with a 1-day history of faint erythema on her face. She had been treated with oral celecoxib (400 mg/day for 7 days) [time to reaction onset not clearly stated] and erlotinib for pain and control of lung cancer, which had been diagnosed 10 months earlier. Laboratory analysis revealed a slightly elevated WBC count and CRP level. A drug eruption due to celecoxib or erlotinib was considered, but treatment was maintained. Topical betamethasone was initiated but, 3 days later, the erythemas had developed over her whole body; a skin biopsy was taken.Celecoxib and erlotinib were withdrawn. Within 10 days of treatment with olopatadine, difluprednate and hydrocortisone butyrate, the erythema had resolved. Histopathological analysis revealed a mild inflammatory infiltrate with subepidermal oedema in the upper dermis, and partial liquefaction degeneration at the dermalepidermal interface with a lymphocytic infiltrate. Patch testing was positive for celecoxib, and an erythema multiforme-type drug eruption due to celecoxib was diagnosed. Erlotinib was reintroduced, with no further symptoms indicating a drug eruption.Arakawa Y, et al. Celecoxib-induced erythema multiforme-type drug eruption with a positive patch test.