Insulin injection can lower blood sugar. For diabetic patients with long-term hyperglycemia, lowering blood sugar reduces the possibility of them suffering from various complications caused by hyperglycemia. At the same time, if insulin injection is used to control blood sugar , diabetics can also eat and drink appropriately. However, the dose of injection must be grasped. If the dose is not grasped and too much injection is made, blood sugar will drop too much. Hypoglycemia can also be very harmful to diabetics.