Mefenamic acid-triggered drug reaction with eosinophilia and systemic symptoms syndrome: A diagnostic challenge

Drug reaction with eosinophilia and systemic symptoms (DRESS) is a potentially fatal hypersensitivity reaction characterized by rash, fever, hematological abnormalities, lymphadenopathy, and multi-organ involvement. Non-steroidal anti-inflammatory drug-induced DRESS is rare, and identification of the culprit drug can be challenging, particularly when over-the-counter (OTC) combination formulations are involved. We report a case of a 30-year-old female who developed DRESS after taking a fixed-dose OTC combination of mefenamic acid and dicyclomine for dysmenorrhea and abdominal pain. This case underscores the need for heightened clinical vigilance regarding OTC analgesic use and supports cyclosporine as an effective steroid-sparing treatment option in DRESS.