Cross-Reactivity: a Case of Paracetamol-Induced Generalized Bullous Fixed Drug Eruption Followed by Dipyrone-Induced Fixed Drug Eruption

A fixed drug eruption (FDE) is a recurring adverse drug reaction that manifests as lesions on the same cutaneous or mucosal sites after exposure to the causative drug. It is characterized by erythematous or violaceous, round-to-oval patches with a dusky center. With each recurrence, the number and size of lesions can increase, raising the risk for generalized bullous fixed drug eruption (GBFDE). GBFDE, a rare and severe variant, presents with widespread bullae accompanied by characteristic FDE lesions. Nonsteroidal anti-inflammatory drugs (NSAIDs) are among the primary causes of FDE. Although cross-reactivity between different groups of NSAIDs has been rarely reported in FDE cases, in this report we present a case of paracetamol-induced GBFDE followed by FDE triggered by cross-reactivity with dipyrone (metamizole).