A basic metabolic panel (BMP) measures the essential metabolic components of your blood. A comprehensive metabolic panel (CMP) measures substances produced by your liver in addition to the basic components of a BMP.
The basic metabolic panel (BMP) and comprehensive metabolic panel (CMP) tests are both blood tests that measure levels of certain substances in your blood.
A doctor may order either a BMP or CMP during a physical or check-up. Abnormally elevated levels of one or more substances in your blood may result from a condition that can be treated.
These tests are used for different reasons. A BMP test gives your doctor information about:
- blood urea nitrogen (BUN), or how much nitrogen is in your blood to measure kidney function
- creatinine, another indicator of kidney function
- glucose, or blood sugar (having high or low blood sugar could both indicate pancreatic issues)
- carbon dioxide (CO2), or bicarbonate, a gas that can indicate issues with your kidneys or lungs
- calcium, which can indicate bone, kidney, or thyroid issues (though sometimes not included in a BMP)
- sodium and potassium, minerals that indicates your body’s overall fluid balance
- chloride, an electrolyte that indicates fluid balance
A CMP test includes all the previous tests as well as tests for:
- albumin, a protein that can indicate liver or kidney issues
- total protein, which accounts for overall blood protein levels
- alkaline phosphatase (ALP), a liver enzyme that can indicate liver or bone conditions
- alanine amino transferase (ALT or SGPT), an enzyme in your kidneys and liver that can indicate liver damage
- aspartate amino transferase (AST or SGOT), an enzyme in liver and heart cells that can also indicate liver damage
- bilirubin, created when your liver naturally breaks down red blood cells
Read on to learn more about how blood samples are collected, how to understand the test results, and how much these tests might cost.
Many medical facilities are licensed to collect blood. But your doctor will most likely refer you to a laboratory that specializes in blood tests.
To take a blood sample, your doctor or a laboratory technician uses a needle to remove a small amount of blood and store it in a tube for analysis. This process is known as venipuncture. One blood sample can be used to test for all 14 substance.
Before either of these tests, you’ll need to fast. What you eat and drink can affect the levels of many substances in your blood, and fasting ensures an accurate measurement not affected by food.
If you’re sensitive to needles or the sight of blood, have someone take you to the lab so that you can safely return afterward.
The BMP is primarily used to look for:
- electrolyte imbalance
- abnormal blood sugar
- how well your blood is being filtered
Abnormal levels can indicate kidney or heart conditions.
The CMP also measures levels of substances produced by your liver. It can indicate:
- how well your liver is functioning
- what the protein levels are in your blood
The additional substances measured by the CMP test essentially allow a closer look at your liver function and its relation to your bones and other organs. This test may be chosen over the BMP if:
- your doctor believes you may have a liver condition
- you’re already being treated for a liver condition and your doctor wants to monitor the results of treatment
Results from a BMP are as follows. High or low levels of each of these components can indicate underlying conditions.
Test | Normal range by age (in years) |
BUN | • 16–20 milligrams per deciliter (mg/dL) of blood (18–60) • 8–23 mg/dL (over 60) |
creatinine | • 0.9–1.3 mg/dL (men 18–60) • 0.8–1.3 mg/dL (men over 60) • 0.6–1.1 (women 18–60) • 0.6–1.2 mg/dL (women over 60) |
glucose | • 70–99 mg/dL (all ages) |
albumin | • 3.4–5.4 grams per deciliter (g/dL) (all ages) |
CO2 | • 23–29 milliequivalent units per liter of blood (mEq/L) (18–60) • 23–31 mEq/L (61–90) • 20–29 mEq/L (over 90) |
calcium | • 8.6–10.2 mg/dL (all ages) |
sodium | • 136–145 mEq/L (18–90) • 132–146 mEq/L (over 90) |
potassium | • 3.5–5.1 mEq/L (all ages) |
chloride | • 98–107 mEq/L (18–90) • 98–111 (over 90) |
BUN
High levels may mean that you have kidney problems, which could include kidney failure or glomerulonephritis, an infection of the part of your kidneys’ blood filters (the glomeruli).
Low levels can mean you’re not getting enough protein in your diet or you have a liver condition.
Creatinine
High levels may mean that you have muscle or kidney conditions, or preeclampsia, a dangerous condition that can happen during pregnancy.
Low levels may mean that your muscles are abnormally weak.
Blood sugar
High levels may mean you have diabetes, pancreatic conditions, or abnormal thyroid enlargement.
Low levels can mean that your thyroid, pituitary, or adrenal glands aren’t functioning properly.
Albumin
Having high albumin isn’t common. Low levels can result from not getting enough protein, having liver or kidney conditions, or having recently had bariatric surgery to lose weight.
CO2
High levels can mean you’re not breathing properly or that you’re having issues with your metabolism or hormones.
Low levels can mean that you have a kidney condition, poison in your blood, or too much acid in your body (acidosis).
Calcium
High levels can mean that you have a type of parathyroid gland cancer.
Low levels may mean that you have:
- pancreatic issues
- liver or kidney failure
- parathyroid dysfunction
- lack of vitamin D in your blood
Sodium
High levels can mean that you have:
- Cushing’s syndrome, which results from too much cortisol in your blood for an extended period
- diabetes insipidus, a type of diabetes that makes you extremely thirsty and urinate more than usual
Low levels can mean that you:
- are dehydrated
- have vomited recently
- have kidney, heart, or liver failure
- have syndrome of inappropriate hormone secretion (SIADH)
- have Addison’s disease, which happens when your adrenal gland doesn’t get enough hormones
Potassium
High levels can mean that you have a kidney condition or issues with heart function.
Low levels can result from hormonal issues or from taking a diuretic to help pass fluid waste.
Chloride
High levels can mean that your kidneys aren’t filtering enough acid from your body.
Low levels can result from Addison’s disease, dehydration, or congestive heart failure (CHF).
ALP
High levels can indicate:
Low levels may result from:
- heart surgery
- zinc deficiency
- malnourishment
- bone metabolism disorders
ALT
High levels can indicate:
- hepatitis
- liver cancer
- cirrhosis
- liver damage
Low ALT levels are normal.
AST
High AST levels can indicate:
- mononucleosis (or mono)
- hepatitis
- cirrhosis
- pancreatitis
- heart conditions
Low AST levels are normal.
Bilirubin
High levels can indicate:
- Gilbert’s syndrome, a harmless condition where your body doesn’t produce enough of an enzyme to lower bilirubin levels
- abnormal red blood cell destruction (hemolysis)
- adverse medication reactions
- hepatitis
- bile duct blockage
Both the BMP and CMP tests may be free as part of your health insurance plan’s preventive care coverage, which is often covered at 100 percent. One test per year may be fully covered, but further tests may only be partially covered or not covered at all.
Costs without insurance may vary widely.
- BMP: $10–$100
- CMP:$200–$250
The CMP tests additional liver substances, so you may not need a CMP test if your doctor isn’t concerned about your liver function. The BMP test is likely enough if you simply want a basic overview of the essential metabolic components of your blood.
If your doctor suspects a liver condition or finds abnormal values in your BMP test, you may need the CMP to diagnose an underlying condition that must be treated.