ALLERGIC reactions to insulin may be local or generalized. Local reactions are said to occur in 5%-30% of insulin-treated patients 1 and are characterized by redness, heat, pain, pruritus, and swelling at injection sites. Generalized reactions are uncommon and may appear as generalized rashes,2 gastrointestinal disorders,3 serum sickness, and even anaphylaxis.4
It is the present purpose to report five cases of insulin allergy and to describe certain observations on the use of insulins from various species, including human, and on the use of dealaninated pork insulin.
Intradermal tests were performed by injecting 0.1 ml of each test substance intradermally into the upper back. The injected sites were examined at 15, 30, and 60 minutes for the development of erythema, induration, and pseudopods, and the results were graded as follows:0—erythema or induration, or erythema and/or induration at 15 min disappearing by 30 min.1+—Induration of less