Why should insulin glargine not be administered intravenously in ICU settings?

Insulin glargine should not be administered intravenously in ICU settings primarily because it can form harmful crystals in the body. Insulin glargine is specifically designed to be a long-acting insulin with a unique formulation that allows for a gradual release into the bloodstream when injected subcutaneously. When administered intravenously, the behavior of the insulin can change; it may precipitate or crystallize, leading to complications that can result in tissue damage or ineffective glucose control.

The alternative route of administration is intended for specific long-term glucose management and can disrupt the expected pharmacokinetics, potentially leading to adverse effects. The formation of crystals from insulin glargine when given IV could create blockages or other issues that would undermine proper insulin function and lead to clinical complications in a critical care environment. It's vital for healthcare providers to use insulin glargine according to its intended route to ensure patient safety and effective glucose management.