Metabolic panel results: what a BMP and a CMP measure and typical ranges
A metabolic panel is a group of blood tests on one sample. A basic metabolic panel (BMP) measures 8 substances and a comprehensive metabolic panel (CMP) measures 14, giving a picture of your blood sugar, fluid and salt balance, kidneys and, for the CMP, liver and blood proteins. (MedlinePlus BMP) (MedlinePlus CMP)
What each part measures
- Glucose: a sugar that is your body's main source of energy. A high level may be a sign of diabetes. (MedlinePlus BMP) The fasting ranges for prediabetes and diabetes, and how they compare with an A1C, are on A1C and blood sugar test results.
- Electrolytes (sodium, potassium, chloride and carbon dioxide, also called bicarbonate): charged minerals that help control the amount of fluid in your body and its acid and base balance, and help nerves, muscles and the heart work. (MedlinePlus BMP) (MedlinePlus CMP)
- Calcium: a mineral needed for your nerves, muscles and heart to work properly; most of the body's calcium is stored in bones and teeth. (MedlinePlus CMP)
- BUN and creatinine: waste products that your kidneys filter out of your blood. (MedlinePlus CMP) The lab combines creatinine with factors such as age and sex to estimate how well your kidneys filter (eGFR). (MedlinePlus GFR) What an eGFR result means: kidney test results.
- Albumin and total protein (CMP only): albumin is the main protein in your blood and is made in the liver; total protein is albumin plus the other blood proteins, called globulins. (MedlinePlus CMP)
- ALP, ALT and AST (CMP only): enzymes made mainly in the liver. (MedlinePlus CMP) ALT and AST are also two of the numbers in the FIB-4 liver scarring score: fatty liver screening and FIB-4.
- Bilirubin (CMP only): a waste product made when old red blood cells break down; the liver removes most of it. (MedlinePlus CMP)
Is it a screening test?
A basic or comprehensive metabolic panel is not on the USPSTF list of recommended (A and B) services for adults without symptoms. (USPSTF A and B list) MedlinePlus notes that both are often done as part of a regular checkup, and they are also ordered for symptoms such as tiredness, confusion or long-lasting vomiting, or to follow a long-term condition such as high blood pressure or kidney disease. (MedlinePlus BMP) (MedlinePlus CMP) The blood tests the USPSTF does recommend, by age: blood tests by age.
The test and fasting
A health care professional takes a small sample of blood from a vein in your arm, which usually takes less than five minutes. (MedlinePlus BMP) You may be asked not to eat or drink for 8 hours before a BMP or CMP. (MedlinePlus encyclopedia BMP) (MedlinePlus encyclopedia CMP) Follow the instructions you were given; see fasting before a blood test.
Typical adult ranges, and why they differ
Even pages from the same publisher print slightly different ranges, as the table shows. Labs use different methods, so they set their own reference ranges from results in large groups of healthy people. Compare your result with the range on your own lab report, and use the same lab if you want to follow a trend. (MedlinePlus lab results)
- Creatinine varies with a person's size and muscle mass, which is why women often have lower levels than men. (MedlinePlus creatinine)
- ALP also varies with age and sex. High levels are normal in children during growth spurts and in pregnancy. (MedlinePlus ALP)
- Glucose: the fasting range applies only if you fasted; after eating, a normal level depends on when you last ate. (MedlinePlus glucose)
- Units: some labs report in other units, such as mmol/L for glucose or micromoles per liter for creatinine; the pages above give both. (MedlinePlus encyclopedia BMP) (MedlinePlus encyclopedia CMP)
What a high or low flag can mean
These are the general kinds of reasons the sources list. They are possibilities to look into, not a diagnosis. Abnormal results overall can come from conditions such as kidney disease, liver disease, breathing problems, diabetes or medicine side effects. (MedlinePlus encyclopedia BMP) (MedlinePlus encyclopedia CMP)
- Sodium: can be high with fluid loss, for example from heavy sweating or diarrhea, or not drinking enough; and low with vomiting or diarrhea, extra body water in heart, kidney or liver disease, or very high blood sugar. Some medicines and hormone problems change it too. (MedlinePlus sodium)
- Potassium: can be high with kidney problems, some medicines or the breakdown of red cells; and low with vomiting, diarrhea or some medicines. (MedlinePlus potassium)
- CO2 and chloride: these move with the body's acid and base balance, so they can change with vomiting, diarrhea, dehydration, kidney disease or lung problems. (MedlinePlus CO2) (MedlinePlus chloride)
- Calcium: a high level can come from an overactive parathyroid gland, long bed rest, too much calcium or vitamin D, or some cancers; a low level from a low albumin, kidney or liver disease, low vitamin D or an underactive parathyroid gland. (MedlinePlus calcium)
- BUN and creatinine: can be high with kidney problems, dehydration or a blocked urinary tract; BUN can also rise with bleeding in the gut or heart failure, and creatinine with muscle breakdown. BUN can be low with liver disease even when the kidneys are normal. (MedlinePlus BUN) (MedlinePlus creatinine)
- Albumin and total protein: can be low with liver or kidney disease or when the body does not get or absorb enough nutrients; albumin can be high with dehydration. Total protein can be high with long-term inflammation or infection, and may rise in pregnancy. (MedlinePlus albumin) (MedlinePlus total protein)
- ALT and AST: a raised level is often a sign of liver disease, such as hepatitis or fatty liver, and more likely so when other liver tests are also raised. AST can also rise with muscle injury, a heart attack or exercise. (MedlinePlus ALT) (MedlinePlus AST)
- ALP and bilirubin: a high ALP can come from the liver or the bile ducts but also from bone, such as a healing fracture. (MedlinePlus ALP) (MedlinePlus liver tests) A high bilirubin can come from liver problems or from red blood cells breaking down faster than normal. (MedlinePlus bilirubin)
Your provider reads the results together, looking for patterns, and also considers your symptoms, history and medicines. If you were ill recently, some abnormal results may be temporary, and the test may be repeated. (MedlinePlus liver tests) (MedlinePlus CMP) More tests are often needed to confirm or rule out a diagnosis. (MedlinePlus BMP) It is common for healthy people to have some results outside the range, and a normal result is not a guarantee of good health. (MedlinePlus lab results) Your doctor decides what your result means for you.
Where they differ: on whether to test, the USPSTF does not list a metabolic panel among its recommended services for adults without symptoms, (USPSTF A and B list) while MedlinePlus describes both panels as often part of a regular checkup that may find problems before symptoms. (MedlinePlus BMP) (MedlinePlus CMP) On the numbers, the ranges for glucose, sodium, chloride, calcium, creatinine, total protein and ALP differ between MedlinePlus pages, as the table shows. Your own lab's range is the one your result is read against. (MedlinePlus lab results)
This page does not give diagnosis, diet, medicine or treatment advice. If you have a flagged result, see after an abnormal screening result for questions to ask.
Questions people ask
What is the difference between a BMP and a CMP?
A basic metabolic panel measures 8 things: glucose, calcium, sodium, potassium, carbon dioxide (bicarbonate), chloride, BUN and creatinine. A comprehensive metabolic panel adds 6 more: albumin, total protein, ALP, ALT, AST and bilirubin, which give more information about the liver and blood proteins. (MedlinePlus BMP) (MedlinePlus CMP)
Do I need to fast for a metabolic panel?
Often, yes. MedlinePlus says you may need to go without food or drink for about 8 hours for a BMP, and for several hours for a CMP. Follow the instructions you were given, because they depend on what else is being tested. (MedlinePlus BMP) (MedlinePlus CMP) (MedlinePlus encyclopedia BMP)
Is a metabolic panel a routine screening test?
Not under the USPSTF: a basic or comprehensive metabolic panel is not on its list of recommended (A and B) services for adults without symptoms. MedlinePlus notes it is often done as part of a regular checkup, and it is also ordered for symptoms or to follow a long-term condition. (USPSTF A and B list) (MedlinePlus BMP) (MedlinePlus CMP)
What does a high creatinine or BUN mean?
Both are waste products the kidneys filter out, so higher levels can point to a kidney problem. They can also rise with dehydration, and creatinine varies with muscle mass. Creatinine is used to estimate how well the kidneys filter (eGFR), which is explained on our kidney test results page. (MedlinePlus CMP) (MedlinePlus BUN) (MedlinePlus creatinine) (MedlinePlus GFR)
Does one abnormal value mean I am ill?
Not always. Healthy people sometimes have results outside the reference range, and some changes are temporary after a recent illness. Your provider compares all the results together, with your history and medicines, and may repeat a test. Your doctor decides what your result means for you. (MedlinePlus lab results) (MedlinePlus liver tests) (MedlinePlus CMP)