Skip to content

Bicarbonate Concentration in Serum or Plasma

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

This test measures the amount of bicarbonate, a key chemical in your blood that helps balance acidity and alkalinity.

Quick summary

["Bicarbonate helps regulate your body’s pH and supports normal metabolism."]

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

Key facts at a glance

LOINC
95271-3
Short code
HCO3 p SCT Fld-sCnc
Synonyms
HCO3 p SCT Fld-sCnc
Category
chemistry
Sample
serum
Container
Red-top tube (SST)
Units
N/A
Ref low
22
Ref high
28
Fasting
false
Population
adult
Sex
all
Age range
18–65 years
Specimen volume
5 mL
Stability
Room temperature: 4h, Refrigerated: 24h, Frozen: 7d
Hemolysis max
500
Lipemia max
1000
Icterus max
500
TAT
4–24 hours
Order
routine

Why Is This Test Done?

Your doctor may order this test to check for conditions affecting acid-base balance, such as metabolic acidosis or alkalosis, or to monitor kidney function, diabetes, or other metabolic disorders. It’s also used in cases of suspected dehydration, heart disease, or respiratory issues.

What Does a Result Mean?

Results are not provided with specific reference ranges here, as they vary by lab and health status. Your doctor will interpret the result in relation to your overall health and symptoms.

How Is the Test Performed?

A blood sample is drawn from a vein, usually in your arm. The sample is sent to a lab where it’s analyzed to measure bicarbonate concentration.

What Are Common Conditions Monitored?

Low bicarbonate levels may indicate metabolic acidosis (e.g., from kidney problems, diabetes, or dehydration). High levels may suggest metabolic alkalosis (e.g., from vomiting, excessive antacid use, or overuse of diuretics).

Reference range

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

Specimen: serum

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.

Clinical Significance: Bicarbonate plays a critical role in maintaining blood pH. Abnormal levels can signal underlying health issues, such as kidney disease, heart conditions, or metabolic disorders. Your doctor will use this test alongside other factors to guide treatment.

Short name

Bicarbonate Level

Frequently asked questions

What does a bicarbonate test measure?
It measures the concentration of bicarbonate ions in your blood, which helps balance acidity and alkalinity.
Can I eat or drink anything before the test?
Typically, no special preparation is needed, but follow your doctor’s instructions. Avoid alcohol or caffeine before testing if advised.
How long does it take to get results?
Results are usually available within 1–2 days, depending on your lab’s processing time.
  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