What is a comprehensive metabolic panel?
Last updated September 3, 2026.
A CMP measures 14 substances from one draw - glucose, calcium, electrolytes, kidney markers, liver enzymes, and protein - a systems snapshot of your body's chemistry. It screens at physicals, monitors conditions like diabetes and hypertension, and checks organ function around medications. You may be asked to fast first; the order will say. Your doctor reads the pattern, since a cluster of values tells a story one number cannot.
What to do
- Check whether fasting applies. Some CMPs require several hours without food - the order states it.
- Know the four storylines. Sugar, kidneys, liver, electrolytes - most questions about a CMP map to one.
- Do not panic over one flag. Mildly out-of-range values are common and often meaningless alone.
- Repeat when asked. Trend lines over two draws beat any single result.
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