Human insulin is used to control blood sugar in people who have type 1 diabetes (condition in which the body does not make insulin and therefore cannot control the amount of sugar in the blood) or in people who have type 2 diabetes (condition in which the blood sugar is too high because the body does not produce or use insulin normally) that cannot be controlled with oral medications alone. Human insulin is in a class of medications called hormones. Human insulin is used to take the place of insulin that is normally produced by the body