Insulin has the following main uses: 1, lowering blood sugar: insulin is a glucose-lowering hormone, so the biggest role is to lower blood sugar. Patients can choose suitable short-acting, medium-acting or long-acting insulin to help control blood sugar throughout the day; 2. Eliminate ketones and lower blood sugar: For patients with diabetic ketosis or acidosis, they can choose suitable doses of insulin for intravenous injection according to their weight and blood sugar, which can achieve the effect of eliminating ketone bodies and lowering blood sugar; 3. Improve low blood potassium: If they belong to patients with high potassium, glucose can be added to insulin to promote potassium ions from extracellular into intracellular, to improve the symptoms of hypokalemia.