Creatine Phosphokinase (CPK/CK) is an enzyme found mainly in heart, brain, and skeletal muscle.

The NAC (N‑acetyl cysteine) activated method is a standardized technique for measuring CK activity.

Clinical uses include:

Diagnosing acute myocardial infarction (heart attack).

Detecting muscle damage due to trauma, strenuous exercise, or muscular dystrophy.

Monitoring drug‑induced myopathy (e.g., statins).

Supporting evaluation of neuromuscular disorders.

Often performed alongside CK‑MB, Troponin, and LDH tests for cardiac assessment.

Analyte: Creatine Phosphokinase (CK) enzyme activity in serum.

Normal Range (varies by lab):

Men: ~55–170 U/L

Women: ~30–135 U/L

Abnormal Findings:

Elevated CK: Suggests muscle injury, myocardial infarction, rhabdomyolysis, or neuromuscular disease.

Very high levels: Seen in severe trauma, muscular dystrophy, or extensive myocardial damage.

Clinical Use:

Provides a sensitive marker of muscle and cardiac injury.

Helps guide diagnosis, monitoring, and treatment planning.

Supports cardiology, neurology, orthopedics, and internal medicine evaluations.