Abstract
Insulin is the cornerstone of type 1 diabetes mellitus (T1DM) treatment. Insulin allergy in patients with T1DM on insulin is an uncommon problem that might manifest itself as immediate or delayed symptoms after injections. We present 2 cases: the first is a 17-year-old girl who was diagnosed with T1DM at the age of 14 and has had several skin lesions at injection sites over the past 2 months that have not responded to antibiotics. The second case involves a 4-year-old boy who was diagnosed with T1DM at the age of 15 months and had non-tender, erythematous, and indurated lesions. Insulin hypersensitivity was detected in both cases, thus newer analogues were administered instead of regular and isophane insulin, and the lesions dramatically reduced.