What is the CPK (CK-NAC) Test?

The CPK (CK-NAC) Test measures the concentration of Creatine Kinase (CK), also known as Creatine Phosphokinase (CPK), an enzyme found mainly in the heart, skeletal muscles, and brain. When these tissues are damaged, CK levels increase in the bloodstream. The NAC method provides accurate measurement of total CK and is commonly used to diagnose muscle disorders, evaluate muscle injury, and monitor recovery after treatment.

Who should take this test?

• Individuals with muscle pain, weakness, or stiffness.
• Patients with suspected muscular dystrophy or inflammatory muscle disease.
• People with suspected rhabdomyolysis (severe muscle breakdown).
• Individuals with chest pain when muscle injury needs evaluation.
• Patients taking statin medications who develop muscle-related symptoms.
• Doctor-recommended monitoring of muscle disorders or muscle injury.

Preparation & Test Process

Understanding Your Results

High CK (CPK) levels may indicate muscle injury, muscular dystrophy, rhabdomyolysis, inflammatory muscle diseases, heart muscle injury, seizures, or recent strenuous exercise.

Normal CK levels generally suggest there is no significant ongoing muscle damage.

Additional investigations such as CK-MB, Troponin, CPK Isoenzymes, ECG, or other muscle-related tests may be recommended depending on your symptoms.

Results should always be interpreted together with your clinical history, symptoms, medications, and other laboratory findings.

FAQs – CPK (CK-NAC) Test