CO2

A carbon dioxide (CO2) blood test measures the amount of carbon dioxide in your blood. Carbon dioxide is an odorless, colorless gas. It is a waste product from metabolism, the process your body uses to make energy from food you eat.

A CO2 blood test is often part of a group of tests called an electrolyte panel, which may be part of a routine checkup. The test may also help diagnose or monitor conditions related to an electrolyte imbalance. These may include high blood pressure and diseases of the kidneys, lungs, or liver.

Source: MedlinePlus, U.S. National Library of Medicine

Normal range

6 published ranges, each from a named source

2330 mEq/L drawn: all ages · American Board of Internal Medicine (Laboratory Test Reference Ranges)

Normal: 23–30 mEq/L

Ranges from American Board of Internal Medicine (Laboratory Test Reference Ranges), LabCorp Test Directory.

All source ranges (6)

Source	Sex	Age	Range
American Board of Internal Medicine (Laboratory Test Reference Ranges)	All	all ages	23–30 mEq/L
LabCorp Test Directory	All	≤ 30 d	16–29 mmol/L
LabCorp Test Directory	All	1 mo – 1 y	15–25 mmol/L
LabCorp Test Directory	All	2 y – 5 y	17–26 mmol/L
LabCorp Test Directory	All	6 y – 12 y	19–27 mmol/L
LabCorp Test Directory	All	12 y+	20–29 mmol/L

What an abnormal result can be associated with

A high result: Hypercapnia
A low result: Hypocapnia

Associations from LOINC2HPO (Human Phenotype Ontology). This is reference information, not a diagnosis: only a clinician can interpret your result in context.

details

Sample: Serum or plasma · LOINC
Part of: Electrolytes panel
Listed under: Fluid and Electrolyte Balance
Code: LOINC 2028-9 · mEq/L
Also known as: Carbon dioxide, total, CO2, CO2 TOTAL, CO2CT, Carbon dioxide

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