Comprehensive Metabolic Panel (CMP)
Reviewed
Also called: chem 14, chemistry panel, chemistry screen, metabolic panel
A comprehensive metabolic panel (CMP) is a routine blood test that measures 14 different substances in a sample of your blood.
Specimen: Blood sample from a vein in your arm
Why this test may be ordered
- As part of a routine checkup
- To check liver and kidney health
- To help diagnose symptoms such as fatigue
- To monitor treatment for certain medical conditions
- To follow up on an abnormal previous CMP result
Preparation and collection
You may need to fast (not eat or drink) for several hours before the test.
A health care professional will take a blood sample from a vein in your arm, using a small needle. After the needle is inserted, a small amount of blood will be collected into a test tube or vial. You may feel a little sting when the needle goes in or out. This usually takes less than five minutes.
There is very little risk to having a blood test. You may have slight pain or bruising at the spot where the needle was put in, but most symptoms go away quickly.
Understanding results
The results of your CMP test will usually list the levels of each of the 14 substances that were measured. To understand what your results mean, your provider will compare all the results.
- One or more results outside normal range: In general, if you have one or more results that aren't normal, it may be a sign of a health condition. Limitation: Your provider will also consider your health history, any medicines you take, and other things that could affect your test results. Next step: You will likely need more tests to confirm or rule out a specific diagnosis.
- High blood glucose: For example, high blood glucose may be a sign of diabetes. Limitation: Your provider will also consider your health history, any medicines you take, and other things that could affect your test results. Next step: You will likely need more tests to confirm or rule out a specific diagnosis.
- A CMP provides a snapshot of your metabolism but does not diagnose specific conditions on its own.
- Abnormal results may be due to medications, diet, or temporary factors.
- False positives or negatives are possible; confirmatory tests are often needed.
- Reference ranges may vary between laboratories; your provider will interpret results based on the lab's range.
What to do next
Ask your provider to explain what your CMP results say about your health. If you have questions about your results, talk with your provider.
- Do I need to fast before the test, and for how long?
- What medications or supplements might affect my CMP results?
- What do my specific results indicate about my liver and kidney function?
- Will I need additional tests based on these results?
- How often should I have a CMP done?
Evidence source
Source: U.S. National Library of Medicine (MedlinePlus). Practices and reference ranges may differ in your country.
U.S. National Library of Medicine: Comprehensive Metabolic Panel (CMP)