Which insulin is described as rapid-acting and suitable for IV use?

Regular insulin is classified as a rapid-acting insulin that is specifically suitable for intravenous (IV) administration. This characteristic is significant in clinical settings where patients require immediate glycemic control, such as in cases of diabetic ketoacidosis or hyperglycemic crises. Regular insulin has a quick onset of action, typically within 30 minutes, and its effects can last for several hours, making it an ideal choice for IV use. Additionally, it is the only form of insulin that is approved for IV administration, allowing healthcare providers to closely monitor and control blood sugar levels through titration.

In contrast, NPH insulin is an intermediate-acting insulin that cannot be infused via IV due to its prolonged action and potential variability in absorption. Humalog, also known as insulin lispro, is a rapid-acting insulin but it is primarily used in subcutaneous administration and not typically given IV. Lantus (insulin glargine) is a long-acting insulin meant for maintaining baseline insulin levels and is not suitable for IV use due to its slow onset and prolonged duration of action.