Ciprofloxacin-Induced Erythema Multiforme Major Unmasking Systemic Lupus Erythematosus.

Systemic lupus erythematosus (SLE) is an autoimmune disease with diverse clinical manifestations characterized by periods of remission and relapse. This report describes the case of a 24-year-old woman with a history of hypothyroidism who developed erythema multiforme major (EMM) following exposure to ciprofloxacin, an antibiotic in the fluoroquinolone class. Subsequent rheumatologic evaluation confirmed a diagnosis of underlying SLE, supported by positive serologic markers and clinical criteria. This case highlights ciprofloxacin-induced EMM as a trigger for unmasking SLE, diagnosed via the 2019 European League Against Rheumatism/American College of Rheumatology (EULAR/ACR) criteria, and underscores the need for rheumatologic evaluation in drug-induced hypersensitivity reactions. Early recognition and intervention are crucial to managing SLE and preventing long-term complications.