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Home > Health Library > Alkaline Phosphatase Test
An alkaline phosphatase (ALP) test measures the amount of the enzyme ALP in the blood. ALP is made mostly in the liver and in bone with some made in the intestines and kidneys. It also is made by the placenta of a pregnant woman.
The liver makes more ALP than the other organs or the bones. Some conditions cause large amounts of ALP in the blood. These conditions include rapid bone growth (during puberty), bone disease (such as Paget's disease or cancer that has spread to the bones), a disease that affects how much calcium is in the blood (hyperparathyroidism), vitamin D deficiency, or damaged liver cells.
If the ALP level is high, more tests may be done to find the cause. The amounts of different types of ALP in the blood may be measured and used to determine whether a high level is from the liver or bones. This is called an alkaline phosphatase isoenzymes test.
The ALP test is done to:
A health professional uses a needle to take a blood sample, usually from the arm.
The test will take a few minutes.
When a blood sample is taken, you may feel nothing at all from the needle. Or you might feel a quick sting or pinch.
There is very little chance of having a problem from this test. When a blood sample is taken, a small bruise may form at the site.
Each lab has a different range for what's normal. Your lab report should show the range that your lab uses for each test. The normal range is just a guide. Your doctor will also look at your results based on your age, health, and other factors. A value that isn't in the normal range may still be normal for you.
Low levels of ALP can be caused by:
Current as of:
April 13, 2022
Author: Healthwise StaffMedical Review: E. Gregory Thompson MD - Internal MedicineKathleen Romito MD - Family MedicineAlan C. Dalkin MD - Endocrinology
Current as of: April 13, 2022
Author: Healthwise Staff
Medical Review:E. Gregory Thompson MD - Internal Medicine & Kathleen Romito MD - Family Medicine & Alan C. Dalkin MD - Endocrinology
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