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Serum Creatinine Phosphokinase (CPK) Isoenzyme Assay (Total CPK)

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

This test measures the total amount of Creatine Phosphokinase (CPK), an enzyme found in heart, muscle, and brain tissues. CPK helps convert creatine phosphate to adenosine triphosphate (ATP), which is essential for energy production.

Quick summary

["CPK levels can help diagnose or monitor conditions affecting muscle, heart, or nerve tissues."]

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

Key facts at a glance

LOINC
87555-9
Short code
ENA SS-A + SSB IgG Pnl Ser
Synonyms
ENA SS-A + SSB IgG Pnl Ser
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

What Does This Test Measure?

CPK is an enzyme that plays a key role in energy production in cells. It exists in three main forms (isoenzymes) in the body: CPK-MM (mostly in muscles), CPK-MB (mostly in the heart), and CPK-BB (in the brain). This test measures the total CPK levels in your blood, combining all three isoenzymes. Elevated CPK levels may indicate muscle damage, heart strain, or other conditions affecting these tissues.

Why Might You Need This Test?

Doctors may order a total CPK test to evaluate symptoms such as muscle weakness, chest pain, or unexplained fatigue. It can also be used to monitor conditions like heart attacks, muscle disorders, or nerve diseases. Additionally, it may be checked before certain medical procedures to assess muscle or heart health.

When Are Results Typically Used?

Total CPK results are often used alongside other tests to diagnose or monitor conditions like myocardial infarction (heart attack), muscular dystrophy, or other muscle-related illnesses. High levels may signal acute muscle injury or heart damage, prompting further investigation.

What Can Affect CPK Levels?

Several factors can influence CPK levels, including recent physical activity, muscle trauma, certain medications (like statins), or underlying health conditions. Avoiding strenuous exercise 48 hours before the test can help ensure accurate results.

Clinical interpretation

How abnormal results are interpreted and what conditions they suggest.

◆Associated findings1

Short name

Total CPK

Frequently asked questions

What does a high CPK level mean?
A high CPK level may suggest muscle damage, heart issues, or other conditions affecting these tissues. Your doctor will review the results with other tests and symptoms to determine the cause and next steps.
What should I do if my CPK level is elevated?
If your CPK level is elevated, your doctor may recommend further testing or adjustments to your treatment plan. They could also suggest reducing physical activity or taking medications to manage symptoms, depending on the underlying cause.
Can CPK levels be affected by diet or supplements?
Diet and supplements alone typically do not significantly affect CPK levels. However, certain supplements (like creatine) or medications (like statins) may influence results. Always inform your healthcare provider about all medications or supplements you take before testing.
  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