What is the difference between CK and CPK?

CK and CPK (creatine phosphokinase) are terms often used interchangeably to refer to the same enzyme. Creatine kinase is the enzyme responsible for catalyzing the conversion of creatine and adenosine triphosphate (ATP) into phosphocreatine and adenosine diphosphate (ADP) during muscle contraction. CPK is an acronym derived from creatine phosphokinase. The terms CK and CPK represent the same enzyme, with CPK being a more specific term denoting the measurement of CK activity in the blood. Therefore, there is no significant difference between CK and CPK.