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Bicarbonate Concentration in Blood (Serum/Plasma)

Published: August 9, 2026Updated: August 17, 2026

This test measures the amount of bicarbonate in your blood, which helps balance acidity (pH). It’s often checked alongside other blood chemistry tests.

Quick summary

["Bicarbonate helps regulate your body’s acid-base balance and is key to normal blood function."]

Medically reviewed by WellAlly Editorial TeamLast reviewed August 17, 2026Editorial policy

Key facts at a glance

LOINC
14627-4
Short code
HCO3 BldV-sCnc
Synonyms
HCO3 BldV-sCnc
Category
chemistry
Sample
whole-blood
Container
Lavender-top (EDTA)
Units
N/A
Ref low
22
Ref high
28
Fasting
false
Population
adult
Sex
all
Age range
18–65 years
Specimen volume
3 mL
Stability
Room temperature: 4h, Refrigerated: 24h
Hemolysis max
0
Lipemia max
0
Icterus max
0
TAT
4–24 hours
Order
routine

Why This Test Matters

Your body maintains a delicate balance between acids and bases to keep your organs working properly. Bicarbonate is one of the main ways your blood does this. Abnormal levels can signal conditions like kidney disease, metabolic disorders, or respiratory issues.

How the Test Works

A small blood sample is taken, usually from your arm. The lab measures bicarbonate concentration using a specialized chemical method that detects its presence in the serum or plasma.

Common Conditions Monitored

Doctors may order this test if you have symptoms like fatigue, confusion, rapid breathing, or unexplained muscle weakness. It’s also used to diagnose or monitor conditions like metabolic acidosis or alkalosis, kidney problems, or diabetes.

What to Expect Before the Test

No special preparation is needed, but tell your doctor about any medications (especially diuretics or steroids) or recent illnesses that might affect results. Avoid heavy meals 2 hours before testing.

Reference range

NCBI: HCO3- 22-28 mmol/LN/A

Specimen: whole-blood

No special preparation usually required. Stay well hydrated. Inform your healthcare provider of all medications and supplements you are taking.

Clinical interpretation

How abnormal results are interpreted and what conditions they suggest.

◆Associated findings1

Short name

Bicarbonate Level

Frequently asked questions

How can bicarbonate levels affect my health?
Low bicarbonate levels (acidosis) may indicate problems with your kidneys, lungs, or diabetes. High levels (alkalosis) could suggest overuse of antacids, vomiting, or certain kidney disorders. Your doctor will interpret results in the context of your symptoms and other tests.
What do my test results mean?
Results are compared to a standard range for your age and health. If results are outside the normal range, further testing or evaluation may be needed to identify the underlying cause.
Can I eat or drink before this test?
You can usually eat and drink normally unless your doctor specifies otherwise. Some tests require fasting, but this one does not.
  1. 1
    MedlinePlus — Laboratory TestsSource
  2. 2
    Lab Tests OnlineSource
  3. 3
    Mayo Clinic — Tests & ProceduresSource

Click any link to access the full source. PubMed Central (PMC) links provide free full-text access.

This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.

Medical Disclaimer

This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.

If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.

Medically reviewed by WellAlly Editorial Team Last reviewed August 17, 2026. · Read our editorial policy