Something to Sweat About: Two Cases of Dupilumab-Induced Hyperhidrosis and Bromhidrosis

INTRODUCTION: Atopic dermatitis (AD, eczema) is familial chronic inflammatory skin disease of complex etiology and increasing prevalence. Dupilumab is an IL-4 receptor subunit alpha (IL-4Rα) antagonist that is the first Food and Drug Administration-approved biological therapy for moderate-to-severe adult AD inadequately controlled with topical therapies. Adverse effects reported in the literature include injection site reactions, conjunctivitis, headache, and nasopharyngitis. OBJECTIVE: We report the first cases of hyperhidrosis and bromhidrosis as side effects from dupilumab (Dupixent®) for the treatment of AD. CASE REPORTS: Case 1 is a 20-year-old woman with controlled allergic rhinitis and severe AD reported axillary hyperhidrosis with bromhidrosis, comparable to sweat from high-intensity exercise, with no relief from several different over-the-counter antiperspirants. Case 2 is a 61-year-old woman with history of chronic asthma, allergic contact dermatitis, allergic rhinitis, and AD noticed markedly increased sweating with bromhidrosis that was reminiscent of her menopausal symptomology, about 3 months after initiating dupilimab. DISCUSSION: Traditional immunosuppressive agents and corticosteroids have limited efficacy, numerous side effects, and increased risk of infection. The safety profile and efficacy of the newly approved IL-4Rα antagonist dupilumab may be favorable to oral immunosuppressants, but its use remains limited to severe recalcitrant cases, due to financial implications and lack of long-term safety data and comparative head-to-head trials. CONCLUSION: We report improved outcomes with dupilumab, in addition to unpublished cases of bromhidrosis and hyperhidrosis in 2 patients with AD. This report of additional complications may inspire further clinical research and assist clinicians in considering the option of dupilumab for uncontrolled AD, despite aggressive traditional treatment.