Serum Creatinine is a waste product produced by muscles from the breakdown of a compound called creatine, which is involved in energy production. It is normally filtered out of the blood by the kidneys. Measuring serum creatinine levels helps assess kidney function, as elevated levels may indicate that the kidneys are not working effectively. Normal serum creatinine levels vary based on factors like age, gender, and muscle mass. Typically, levels range from 0.6 to 1.2 milligrams per deciliter (mg/dL) in adults. Regular monitoring of serum creatinine can help detect kidney disease or monitor existing conditions.