What is the normal reference range for alkaline phosphatase?

Alkaline phosphatase is an enzyme widely distributed in tissues such as the liver, bones, intestines, kidneys, and placenta of the human body, and is excreted from the liver into the bile. Under normal circumstances, the normal value for adult males is 45–125 U/L, and for females it is 50–130 U/L. The normal value for minors ranges between 250 U/L and 750 U/L, with specific details as follows:

Generally, the normal value for males is 45–125 U/L; for females it is 50–130 U/L. However, during pregnancy, alkaline phosphatase levels may also rise, reaching up to two to three times the upper limit of the normal range. This is a normal physiological change during pregnancy.

Under normal conditions, the alkaline phosphatase level in children under 1 year of age should be less than 500 U/L, in children aged 1–12 years or those weighing less than 50 kg should be less than 250 U/L, and in adolescents under 15 years of age, the normal value is usually less than 750 U/L.

It should be noted that different hospitals and laboratories may use different testing methods or standards, so the normal reference range for alkaline phosphatase might vary. Therefore, the specific normal range should be based on the reference values provided by the hospital or laboratory conducting the test.