As a medication, insulin is any pharmaceutical preparation of the protein hormone insulin that is used to treat high blood glucose. Such conditions include type 1 diabetes, type 2 diabetes, gestational diabetes, and complications of diabetes such as diabetic ketoacidosis and hyperosmolar hyperglycemic states. Insulin is also used along with glucose to treat hyperkalemia (high blood potassium levels). Typically it is given by injection under the skin, but some forms may also be used by injection into a vein or muscle. There are various types of insulin, suitable for various time spans. The types are often all called insulin in the broad sense, although in a more precise sense, insulin is identical to the naturally occurring molecule whereas insulin analogues have slightly different molecules that allow for modified time of action. It is on the World Health Organizations List of Essential Medicines. In 2019, regular human insulin was the 298th most commonly prescribed medication in the United States, with more than 1 million prescriptions.Insulin can be made from the pancreas of pigs or cows. Human versions can be made either by modifying pig versions or recombinant technology. It comes in three main types: short–acting (such as regular insulin), intermediate-acting (such as neutral protamine Hagedorn (NPH) insulin), and longer-acting (such as insulin glargine). History
Insulin was first used as a medication in Canada by Charles Best and Frederick Banting in 1922.This is a chronology of key milestones in the history of the medical use of insulin.
A similar device, but relying on skin-penetrating "microneedles", was in the animal testing stage in 2015. Intranasal
Intranasal insulin is being investigated. A randomized controlled trial that will determine whether intranasal insulin can delay or prevent the onset of type 1 diabetes in at-risk children and young adults is expected to yield results in 2016. By mouth
The basic appeal of hypoglycemic agents by mouth is that most people would prefer a pill or an oral liquid to an injection. However, insulin is a peptide hormone, which is digested in the stomach and gut and in order to be effective at controlling blood sugar, cannot be taken orally in its current form. The potential market for an oral form of insulin is assumed to be enormous, thus many laboratories have attempted to devise ways of moving enough intact insulin from the gut to the portal vein to have a measurable effect on blood sugar.A number of derivatization and formulation strategies are currently being pursued to in an attempt to develop an orally available insulin. Many of these approaches employ nanoparticle delivery systems and several are being tested in clinical trials. Pancreatic transplantation
Another improvement would be a transplantation of the pancreas or beta cell to avoid periodic insulin administration. This would result in a self-regulating insulin source. Transplantation of an entire pancreas (as an individual organ) is difficult and relatively uncommon. It is often performed in conjunction with liver or kidney transplant, although it can be done by itself.