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Alkaline Phosphatase, Serum/Plasma — Substance Concentration

Published: August 9, 2026Updated: August 16, 2026

Measures alkaline phosphatase in a blood sample to help evaluate liver, bile duct, and bone-related conditions.

Quick summary

["This blood test helps assess alkaline phosphatase activity, which may rise with liver, bile duct, or bone disease."]

Medically reviewed by WellAlly Editorial TeamLast reviewed August 16, 2026Editorial policy

Key facts at a glance

LOINC
2582-5
Short code
A-LH SerPl-sCnc
Synonyms
A-LH SerPl-sCnc
Category
liver
Sample
serum
Container
Red-top tube (SST)
Units
N/A
Ref low
1.5
Ref high
9
Fasting
false
Population
adult
Sex
all
Age range
18–65 years
CPT
83002
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

What is this test?

Alkaline phosphatase is an enzyme found in several body tissues, especially the liver, bile ducts, and bones. This test measures its concentration in serum or plasma, the liquid portion of blood.

Why might I need this test?

A clinician may order this test as part of a liver or bile duct evaluation, when checking bone health, or to investigate symptoms such as jaundice, abdominal discomfort, or unexplained bone pain.

How is the test performed?

A blood sample is drawn from a vein and analyzed in the laboratory. It is often part of a broader metabolic liver panel and may be ordered with other liver-related tests.

How do I prepare for the test?

Fasting is often unnecessary, but follow the instructions provided by your clinician or laboratory. Tell the healthcare team about medicines or supplements you take, because some can affect the result.

Reference range

Follicular: 1.5-9.0 mIU/mLN/A

Specimen: serum

For females: inform if menstrual cycle status. For certain tests, timing within menstrual cycle may matter.

Clinical interpretation

How abnormal results are interpreted and what conditions they suggest.

An elevated result may indicate liver or bile duct disease, increased bone activity, or another condition involving alkaline phosphatase-containing tissues. A lower-than-expected result can occur in some nutritional, liver, or bone disorders. Results should be interpreted with symptoms, medical history, and other laboratory tests.

Short name

Serum/Plasma Alkaline Phosphatase

Frequently asked questions

Is fasting required for this test?
Fasting is often not required, although the laboratory's instructions should be followed. Your clinician may request fasting if this test is being performed with other tests.
What does an elevated alkaline phosphatase result mean?
It may suggest irritation or disease involving the liver or bile ducts, or increased bone activity. It does not identify one specific condition by itself.
Can medicines or supplements affect the result?
Yes. Some medicines and supplements can alter alkaline phosphatase levels, so provide your complete medication and supplement list to your healthcare team.
  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 16, 2026. · Read our editorial policy