What Is a Comprehensive Metabolic Panel?
A Comprehensive Metabolic Panel (CMP) is a group of 14 blood tests ordered together to give your doctor a broad view of your metabolic health. It checks how well your kidneys and liver are functioning, your blood sugar levels, your electrolyte balance, and your protein levels. CMPs are ordered at annual checkups, before starting new medications, and to monitor ongoing conditions like diabetes, kidney disease, and liver disease.
When your CMP results arrive, you'll see 14 individual values. Here's what each one means.
Blood Sugar
Glucose is the first value on a CMP and measures the amount of sugar currently in your blood. Fasting reference ranges are typically 70–99 mg/dL. Values between 100–125 mg/dL suggest prediabetes; 126 mg/dL or higher on two separate tests indicates diabetes. If your CMP was drawn after eating, your glucose will naturally be higher — context matters. For a deeper look at blood sugar monitoring, see our guide on understanding your lab results.
Kidney Function Tests
Creatinine is a waste product your muscles produce and your kidneys filter out. Normal ranges are 0.74–1.35 mg/dL for men and 0.59–1.04 mg/dL for women. Elevated creatinine suggests your kidneys aren't clearing waste efficiently.
Blood Urea Nitrogen (BUN) is another waste product filtered by the kidneys. Normal is 7–20 mg/dL. High BUN, particularly alongside high creatinine, is a key signal of reduced kidney function. However, high BUN can also occur with dehydration or a high-protein diet.
BUN/Creatinine Ratio helps distinguish kidney problems from dehydration. A ratio above 20 often points to dehydration or reduced blood flow to the kidneys; a ratio below 10 may suggest liver disease or malnutrition.
eGFR (Estimated Glomerular Filtration Rate) is calculated from your creatinine, age, sex, and race to estimate how well your kidneys are filtering blood. An eGFR above 60 is generally considered normal; below 60 for three months or more indicates chronic kidney disease. eGFR naturally declines with age, so context matters significantly.
Liver Function Tests
ALT (Alanine Aminotransferase) is an enzyme primarily found in liver cells. Normal is 7–56 U/L. Elevated ALT is a sensitive indicator of liver cell damage — it rises with conditions like non-alcoholic fatty liver disease (NAFLD), hepatitis, and medication side effects.
AST (Aspartate Aminotransferase) is found in the liver but also in the heart, muscles, and kidneys. Normal is 10–40 U/L. AST rises with liver damage but is less liver-specific than ALT. An elevated AST/ALT ratio can help distinguish alcoholic liver disease from other causes.
ALP (Alkaline Phosphatase) is found in the liver, bile ducts, and bone. Normal is 44–147 U/L. Elevated ALP alongside elevated bilirubin often points to bile duct obstruction.
Bilirubin (Total) is the yellow pigment produced when red blood cells break down. Normal is 0.1–1.2 mg/dL. Elevated bilirubin causes jaundice — the yellowing of skin and eyes. It can indicate liver disease, bile duct blockage, or excessive breakdown of red blood cells.
Total Protein measures the combined level of albumin and globulin in your blood. Normal is 6.3–8.2 g/dL. Low total protein can indicate malnutrition, liver disease, or kidney disease.
Albumin is a protein made by the liver that maintains fluid balance and transports nutrients. Normal is 3.5–5.0 g/dL. Low albumin is a sensitive marker of poor liver function or chronic illness. It's also used to calculate a "corrected calcium" value.
Electrolytes
Sodium (Na) regulates fluid balance and nerve function. Normal is 136–145 mEq/L. Low sodium (hyponatremia) can cause confusion and weakness; high sodium (hypernatremia) is often a sign of dehydration.
Potassium (K) is critical for heart and muscle function. Normal is 3.5–5.0 mEq/L. Low potassium (hypokalemia) can cause muscle cramps and dangerous heart arrhythmias. High potassium (hyperkalemia) can also affect heart rhythm.
Chloride (Cl) works alongside sodium to maintain fluid balance. Normal is 98–106 mEq/L. Abnormal chloride often follows sodium and potassium abnormalities.
Carbon Dioxide (CO2 / Bicarbonate) reflects your body's acid-base balance. Normal is 22–29 mEq/L. Low CO2 can indicate acidosis; high CO2 suggests alkalosis.
Calcium (Ca) is needed for bone health, nerve signaling, and muscle contraction. Normal is 8.5–10.2 mg/dL. High calcium (hypercalcemia) can be caused by parathyroid disorders or certain cancers. Low calcium (hypocalcemia) can cause muscle cramps and bone problems.
Putting It All Together
A CMP provides a sweeping view of your metabolic health in a single blood draw. Doctors rarely act on a single abnormal value without repeating the test or ordering follow-up tests. If you're managing a chronic condition, tracking your CMP values over time reveals trends that a snapshot can't capture.
MediSphere™ stores your CMP history and uses AI to highlight trends, explain values in plain language, and help you prepare thoughtful questions for your next appointment. See how AI-powered health insights transform your lab data into actionable knowledge — and visit our For Patients page to learn more.
This article is for educational purposes only. Always discuss your specific results with your healthcare provider.