Introduction: Insulin allergy is a rare clinical situation. The frequency of insulin allergy has decreased since highly purified insulin preparations have been available. It is still a matter of concern and its frequency may have inceased with the last generation of insulin analogues.

Case presentation: We report a51-year-old female patient with type 2 diabetes who required multiple daily insulin injections. The patient developed allergy to human regular insulin and insulin analogs (insulin aspart and insulin glargine), which was resolved by subcutaneous insulin desensitization.

Conclusion: As reported in this case, desensitization with subcutaneously administered human insulin using an ultra-rush protocol in patients with an insulin allergy may present an easy form of therapy that is successful within a few days.