Tralokinumab was initiated in a 17-year-old male with severe AD since childhood, insufficiently controlled with topical steroids and several courses of cyclosporine (baseline Eczema Area and Severity Index [EASI] 23, peak pruritus numeric rating scale [PP NRS] 9/10). Tralokinumab treatment led to remarkable improvement of signs and symptoms of AD (EASI 2, PP NRS 3/10 after 7 months of treatment). However, the patient reported pruritic and painful ISR lasting generally less than 24 h after the initial self-injections at home. He had no fever nor systemic symptoms. At the 16-week follow-up visit, swelling and erythema (i.e., symptoms of ISR) were observed at the site of the last injections made by the patient the previous day. [...]