Creatinine

Creatinine is a byproduct of a chemical compound called creatine, which helps muscles get the energy that they need. As a waste product, creatinine is filtered out of the blood by the kidneys and removed from the body in urine.

A creatinine test measures the amount of this chemical in either the blood or urine. Creatinine levels can provide an indication of how well the kidneys are working.

It may be measured alone or as part of a panel of tests that include other compounds found in the urine or blood.