Comprehensive Metabolic Panel
Does this test have other names?
Metabolic panel, CMP, chem 12, chemistry panel, chemistry screen, (formerly SMAC, sequential multiple analyzer chemistry)
What is this test?
This test is a screening panel of 14 tests that look at your metabolism.
Your body gets energy from food through a process called metabolism. The tests in this panel help see how well your liver and kidneys are working. These are two major organs involved in metabolism.
These tests also measure your electrolyte and acid/base balance, your blood sugar, and your blood proteins. Electrolytes are mineral salts that help move nutrients into your cells and move waste products out of your cells. Electrolytes also help maintain your body's fluid and pH, or acidity, levels.
Most labs perform the same 14 tests, but these may be changed depending on what your doctor is looking for. They may also vary slightly between labs. The 14 tests that are included in most CMPs are:
Albumin, a liver protein
Alkaline phosphatase (ALP)
Alanine aminotransferase (ALT)
Aspartate aminotransferase (AST)
Blood urea nitrogen (BUN)
Carbon dioxide, an electrolyte
Chloride, an electrolyte
Potassium, an electrolyte
Sodium, an electrolyte
Why do I need this test?
You may have this test as part of a routine physical. You may also have this test done to check for kidney and liver diseases, as well as problems caused by diabetes.
If you take medicines for high blood pressure, or other medicines that can affect your kidneys or liver, you may also have this test done to check your kidney and liver function.
What other tests might I have along with this test?
Your doctor may also order other tests to look at how well your liver and kidneys are working. These tests may include:
Your doctor may also order other blood tests to check for iron deficiency, anemia, and other disorders:
What do my test results mean?
Many things may affect your lab test results. These include the method each lab uses to do the test. Even if your test results are different from the normal value, you may not have a problem. To learn what the results mean for you, talk with your health care provider.
Normal findings for the 14 tests are:
Albumin: 3.5 to 5.0 grams per deciliter (g/dL)
ALP: 30 to 120 international units/liter (IU/L)
ALT: 4 to 36 IU/L
AST: 0 to 35 IU/L
BUN: 10 to 20 milligram/per deciliter (mg/dL)
Calcium: 9.0 to 10.5 mg/dL
Carbon dioxide: 23 to 30 millimoles per liter (mmol/L)
Chloride: 96 to 106 mmol/L
Creatinine: 0.5 to 1.1 mg/dL (females), 0.6 to 1.2 mg/dL (males)
Glucose test: less than 110 mg/dL
Potassium test: 3.5 to 5.0 milliequivalents per liter (mEq/L)
Sodium: 136 to 145 mEq/L
Total bilirubin: 0.3 to 1.0 mg/dL
Total protein: 6.4 to 8.3 g/dL
If your results are abnormal or combinations of abnormal levels, it may mean you have problem, such as diabetes, liver disease, or kidney disease. You may need more tests to confirm or rule out specific diagnoses.
How is this test done?
The test requires a blood sample, which is drawn through a needle from a vein in your arm.
Does this test pose any risks?
Taking a blood sample with a needle carries risks that include bleeding, infection, bruising, or feeling dizzy. When the needle pricks your arm, you may feel a slight stinging sensation or pain. Afterward, the site may be slightly sore.
What might affect my test results?
Eating or exercising before the test can affect your results. Taking certain medications, including steroids, insulin, and hormones, also can affect your results.
If you are pregnant or dehydrated, your results may be affected.
How do I get ready for this test?
You should not eat or drink anything but water for 10 to 12 hours before this test. Don't exercise before the test. In addition, be sure your doctor knows about all medicines, herbs, vitamins, and supplements you are taking. This includes medicines that don't need a prescription and any illicit drugs you may use.