Creatinine Kinase, Total (CK) – Serum/plasma
This test measures the total amount of creatinine kinase, an enzyme that helps convert phosphocreatine to creatinine phosphate in cells. It’s important for assessing muscle damage and heart health.
["CK helps diagnose muscle or heart injuries and monitor conditions like myopathy or heart attacks."]
Key facts at a glance
- LOINC
- 2158-4
- Short code
- CK/CK MB SerPl-cRto
- Synonyms
- CK/CK MB SerPl-cRto
- Category
- chemistry
- Sample
- serum
- Container
- Red-top tube (SST)
- Units
- N/A
- Ref low
- 22
- Ref high
- 198
- Critical range
- — – 10000 N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- CPT
- 82553
- Specimen volume
- 5 mL
- Stability
- Room temperature: 4h, Refrigerated: 24h, Frozen: 7d
- Hemolysis max
- 500
- Lipemia max
- 1000
- Icterus max
- 500
- TAT
- 4–24 hours
- Order
- routine
What Is Creatinine Kinase Used For?
Creatinine kinase (CK) is found in high levels in heart, brain, skeletal muscle, and red blood cells. Elevated CK levels may signal muscle damage (e.g., from exercise, injury, or certain medications) or heart-related issues like a heart attack. Doctors may also use CK to monitor conditions like myasthenia gravis or muscle disorders.
Why Might My CK Levels Be High?
High CK levels can occur due to muscle strain (e.g., intense exercise), trauma, infections, or certain medications. In rare cases, elevated CK may indicate heart problems, such as a heart attack, though other tests (like troponin) are often used first for heart-related concerns.
What If My CK Levels Are Low?
Low CK levels are less common but may occur in conditions like severe muscle wasting, certain genetic disorders, or in newborns. Your doctor would discuss this with you based on your medical history and symptoms.
How Is CK Tested?
This test is typically done on a blood sample drawn from a vein. The lab uses an immunoassay method to detect CK levels, which is then compared to a reference range for your age and health status.
Reference range
Adult males: 22-198 U/L; Females: 22-198 U/LN/A
No special preparation required. Inform provider of any chest pain or symptoms.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
CK is a marker for muscle and heart cell damage. While elevated CK alone doesn’t always indicate a serious issue, it can signal underlying problems that require further evaluation. For example, very high CK may prompt additional testing for muscle disorders or heart conditions. Always discuss results with your healthcare provider.
Short name
Total CK
Frequently asked questions
What causes elevated CK levels?
What should I do if my CK levels are elevated?
Can CK levels be affected by diet or supplements?
Sources
- 1
- 2Lab Tests OnlineSource
- 3
Click any link to access the full source. PubMed Central (PMC) links provide free full-text access.
This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.
This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.
If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.
Medically reviewed by WellAlly Editorial Team Last reviewed August 17, 2026. · Read our editorial policy