Cilastatin is a medication that is primarily used to prevent the breakdown of the antibiotic imipenem. It works by inhibiting the enzyme dehydropeptidase, which can inactivate imipenem in the kidneys. By doing so, cilastatin helps to enhance the effectiveness of imipenem, allowing it to remain active in the body for a longer period. Cilastatin is often administered in combination with imipenem to treat serious bacterial infections. This combination is particularly useful for infections caused by resistant bacteria, as imipenem is a broad-spectrum antibiotic. The use of cilastatin ensures that patients receive the full benefits of imipenem without the risk of rapid degradation.