Insulin (medication)
![Insulin vials.](/Images/godic/202501/18/Inzulín3027.jpg")
![Administering insulin with an insulin pen.](/Images/godic/202501/18/Insulin_Application3027.jpg")
![The idealised diagram shows the fluctuation of blood sugar (red) and the sugar-lowering hormone insulin (blue) in humans during the course of a day containing three meals. In addition, the effect of a sugar-rich versus a starch-rich meal is highlighted.](/Images/godic/202501/18/Suckale08_fig3_glucose_insulin_day3027.png")
![Diagram explaining the basal-bolus insulin schedule. The long acting insulin is given once (usually glargine, Lantus) or twice (usually detemir, Levemir) daily to provide a base, or basal insulin level. Rapid acting (RA) insulin is given before meals and snacks. A similar profile can be provided using an insulin pump where rapid acting insulin is given as the basal and premeal bolus insulin.](/Images/godic/202501/18/Insulin_basal_bolus3027.png")
Insulin (medication) is the use of insulin and similar proteins as a medication to treat disease. Insulin comes in a number of different types including short acting (such as regular insulin) and long acting (such as NPH insulin). Insulin is used to treat a number of diseases including diabetes and its acute complications such as diabetic ketoacidosis and hyperosmolar hyperglycemic states. It is also used along with glucose to treat high blood potassium levels. Side effects may include: low blood sugar levels, skin reactions at the site of injection and low potassium levels among others. Insulin was first used as a medication in Canada by Charles Best and Frederick Banting in January 1922.