Oral insulin tablets have not been reported in clinical studies, but oral insulin capsules have been tested. Human insulin is composed of two peptide chains of 51 amino acids from 26 species, and its chemical structure is not resistant to degradation by gastric acid and digestive enzymes, so insulin tablets alone may not be able to achieve glucose-lowering effects. Although there is no report on the clinical application of simple insulin tablets, there are experimental studies on oral insulin capsules, which mainly transport insulin to the intestine through a special capsule device, and then absorbed into the bloodstream through the portal vein to exert a hypoglycemic effect. Therefore, at this stage, patients are advised to follow the doctor’s instructions for reasonable injection of insulin and other blood glucose control.