Paradoxical lichenoid drug eruption following dupilumab use for atopic dermatitis: A case report.

Dupilumab is a monoclonal antibody targeting interleukin-4 (IL-4) and interleukin-13 (IL-13) signaling, approved for moderate-to-severe atopic dermatitis. Although generally well tolerated, paradoxical cutaneous reactions have been reported. We present a case of a 30-year-old male with longstanding atopic dermatitis who developed a lichenoid eruption several weeks after initiating dupilumab therapy. Biopsy confirmed a lichenoid drug eruption, prompting treatment modification. This case contributes to the growing recognition of paradoxical immune-mediated skin reactions associated with biologics and outlines a management approach balancing drug efficacy with adverse effect mitigation.