Itchy skin after taking insulin may be caused by allergy to insulin preparation, if it is insulin allergy, there are several solutions as follows: 1, if it is type 2 diabetes mellitus, you can choose oral hypoglycemic drugs for treatment, one can’t be two or three hypoglycemic drugs can be combined application. 2, you can change another insulin to try. 3, if all the insulin preparation If all the insulin preparations are allergic, and it is necessary to apply insulin treatment for diabetic patients, such as type 1 diabetes mellitus, hepatic and renal insufficiency patients, you can also try to use simple short-acting insulin (which does not have allergic epithelial agents added to it) small-dose multiple injections of desensitization therapy, or use insulin pumps to carry out desensitization therapy. 4, in addition to considering whether the insulin is allergic to the itching of the skin, we should also exclude the possibility that it is due to the lack of sterilization or the use of injectable drugs, or the lack of sterilization. In addition to considering whether the insulin is allergic, the itchy skin should also be excluded to see if it is due to the lack of sterilization, or the long-term non-replacement of insulin needles for injection, so as to solve the problem.