Normal value of serum alkaline phosphatase

The normal values of serum alkaline phosphatase (ALP) vary according to gender and age. Generally, the normal serum ALP level for children (1-12 years old) is usually less than 500 U/L, as children secrete large amounts of alkaline phosphatase during bone growth and development. For adults, the normal range for males (over 25 years old) is typically 45-125 U/L, while for females it varies by age group: 35-100 U/L for women aged 20-49 years, and 50-135 U/L for women aged 50-79 years.

Alkaline phosphatase is widely present in human liver, bone, kidney, and other tissues. It is a common indicator in liver function tests and is also used in the diagnosis of bone and hepatobiliary system diseases. When serum alkaline phosphatase levels are abnormal, it may indicate diseases in the relevant systems, and comprehensive evaluation with other clinical information is required.