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Serum Creatinine Phosphokinase (CPK) Isoenzyme Subtype Analysis (Total CPK)

Published: August 9, 2026Updated: August 16, 2026

This test measures the total activity of creatine kinase, an enzyme found in heart, muscle, and brain cells. It helps assess damage to these tissues, often after injury or illness.

Quick summary

["CPK helps identify muscle, heart, or brain tissue injury by measuring enzyme release into the bloodstream."]

Medically reviewed by WellAlly Editorial TeamLast reviewed August 16, 2026Editorial policy

Key facts at a glance

LOINC
13221-7
Short code
C trach G+F+K IgM Ser-aCnc
Synonyms
C trach G+F+K IgM Ser-aCnc
Category
chemistry
Sample
serum
Container
Red-top tube (SST)
Units
N/A
Fasting
false
Population
adult
Sex
all
Age range
18–65 years
CPT
82784
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

Why This Test Is Done

Your doctor may order this test if you’ve experienced symptoms like muscle pain, weakness, or unusual fatigue. It’s also used to monitor conditions affecting muscle or heart health, such as heart attacks, strokes, or muscle disorders. Sometimes, doctors check CPK levels to evaluate recovery after surgery or trauma.

What to Expect Before the Test

No special preparation is needed. You’ll have a small needle inserted into your arm or hand to draw blood. If you’re taking medications that affect muscle function, let your doctor know. Avoid strenuous activity before the test if instructed.

What the Results Mean

Elevated CPK levels may indicate muscle damage, heart problems, or other conditions. Your doctor will compare your results to your medical history and other tests to determine the cause. Normal results suggest healthy tissue function, but further evaluation may still be needed.

Common Conditions Affecting CPK Levels

High CPK levels can occur with muscle injuries (e.g., strains, cramps), heart attacks, strokes, or certain medications. Low levels are less common but may signal muscle wasting or rare genetic disorders.

Clinical interpretation

How abnormal results are interpreted and what conditions they suggest.

◆Associated findings1

Short name

Total Creatine Kinase (CK) Test

Frequently asked questions

What causes CPK levels to rise?
CPK levels can rise due to muscle damage from exercise, injuries, or conditions like myositis (inflammation of muscles). Heart attacks, strokes, or certain medications (e.g., statins) can also increase CPK. If your doctor suspects a specific issue, they may order additional tests to pinpoint the cause.
How long do elevated CPK levels last?
Elevated CPK levels typically return to normal within days to weeks, depending on the cause. For example, after a muscle injury, levels may peak and drop over a few days. If symptoms persist, your doctor may repeat the test or check for underlying conditions like heart disease.
Can diet or exercise affect CPK levels?
Moderate exercise usually doesn’t significantly affect CPK levels unless you’re pushing your muscles intensely (e.g., marathon training). High-intensity workouts may temporarily raise CPK, but it’s not harmful unless levels stay elevated for long periods. Always follow your doctor’s advice regarding activity levels.
  1. 1
    MedlinePlus — Laboratory TestsSource
  2. 2
    Lab Tests OnlineSource
  3. 3
    Mayo Clinic — Tests & ProceduresSource

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.

Medical Disclaimer

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 16, 2026. · Read our editorial policy