Creatine Kinase
Reviewed
This test measures the amount of creatine kinase (CK) in a sample of your blood. CK is an enzyme that helps make energy. Most of the CK in your body is in your skeletal muscles. Normally, a small amount of CK gets into your blood from the usual wear and tear on your muscles. But if your muscles, heart, or brain tissues are damaged, larger amounts of CK leak out of your cells into your bloodstream. A CK test is mainly used to help diagnose and monitor injuries and diseases that damage skeletal muscles and cause high levels of CK in your blood.
Preparation and collection
You do not need any special preparations. To help make sure your results are accurate, your provider may ask you to avoid intense exercise and drinking alcohol for a few days before your test.
Understanding this test
Use the reference interval and units printed by the laboratory that performed the test. A result outside that interval is not a diagnosis by itself, and a result inside it does not rule out every condition. Your symptoms, history, medicines, timing, and related tests can change what the result means.
- A CK test result cannot show where the damage is or what is causing it.
- CK levels may not reach their highest until up to two days after certain injuries, so you may need more than one test to see if your levels go up or down.
- To diagnose the condition causing high CK levels, you may need other types of tests.
What to do next
Your provider will consider your symptoms and medical history to understand what your test results mean. If the source of high or increasing CK levels is not clear, you may need a more specific type of CK test called a CK isoenzymes test to find out if the CK is coming from your muscles, heart, or brain. To diagnose the condition causing high CK levels, you may need other types of tests, too. The tests you have will depend on which types of CK enzymes are high as well as your symptoms and medical history.