From the Guidelines
Elevated CK levels typically indicate muscle damage or injury, and normal CK ranges are generally 22-198 units/L for men and 24-170 units/L for women, though reference ranges may vary slightly between laboratories. CK levels can rise due to various causes including intense exercise, muscle trauma, certain medications (like statins), heart attacks, or muscle diseases 1. If you're concerned about your CK levels, you should consult with a healthcare provider who can interpret your specific results.
Causes of Elevated CK Levels
- Intense exercise
- Muscle trauma
- Certain medications (like statins)
- Heart attacks
- Muscle diseases According to a recent study, raising CPK levels above five times normal (approximately 1000 IU/L) is a sign of rhabdomyolysis 1. The interpretation of CK levels always needs to be considered alongside your symptoms and medical history, as temporary elevations can occur normally after exercise while persistent high levels may indicate an underlying condition requiring treatment.
Management of Elevated CK Levels
- Rest from strenuous activity
- Staying hydrated
- Avoiding muscle-damaging medications if possible
- Follow-up testing It is essential to note that measurement of total CK is not recommended for the diagnosis of myocardial infarction, because of the large skeletal muscle distribution and the lack of specificity of this enzyme 1. If your CK is elevated, your doctor may recommend further testing, such as troponin or CKMB, to determine the cause of the elevation.
From the FDA Drug Label
Myopathy, defined as muscle aching or muscle weakness in conjunction with increases in creatine phosphokinase (CPK) values to greater than 10 times the ULN, was rare (<0. 1%) in pravastatin clinical trials.
The creatine kinase (CK) levels are not directly stated, but it is mentioned that myopathy is defined as muscle aching or weakness with CPK values greater than 10 times the upper limit of normal (ULN).
- CPK elevations were observed in some patients, particularly those receiving combined treatment with pravastatin and other medications.
- The exact CK levels are not provided in the drug label 2, 2, or 2.
From the Research
Creatine Kinase (CK) Levels
- The normal range for creatine kinase (CK) levels can vary depending on the individual and the laboratory conducting the test 3.
- In one study, the normal range for CK levels was considered to be less than 70 IU/l for female patients and less than 80 IU/l for male patients 3.
- CK-MB mass/total CK activity ratios can be used to differentiate between myocardial necrosis and muscular injury, with a proposed cutoff value of 80 ng/U 4.
- In patients with acute myocardial infarction, the mean maximum CK-MB mass/total CK activity ratio exceeded 200 ng/U 4.
- In patients with muscular damage, the highest CK-MB mass/total CK activity ratio was 38 ng/U, except for an infant who had a ratio of 220 ng/U 4.
CK Levels in Different Conditions
- In patients with acute myocardial infarction, CK levels can be significantly elevated, with peak values often occurring within 12-24 hours after the onset of symptoms 5.
- In patients with skeletal muscle injury, CK levels can also be elevated, but the CK-MB isoform ratio can be used to distinguish between skeletal muscle injury and myocardial infarction 6.
- In patients with neuromuscular disorders, CK levels can be elevated, but this is a relatively rare cause of CK elevation in a medical department 3.
- Other conditions that can cause CK elevation include drug intake, falls, hematomas, intramuscular injections, and malignancies 3.
Measurement of CK Levels
- CK levels can be measured using immunosuppressive assays or mass immunoassays 7.
- The choice of measurement method can affect the results, with immunosuppressive assays potentially giving false positives due to interference 7.
- Mass immunoassays can be used to detect CK-MB and eliminate interference, providing a more accurate measurement of CK levels 7.