🫀 Liver Function

ALP: What It Means for Your Health

Alkaline phosphatase (ALP) is an enzyme found in several tissues, with the highest concentrations in the liver, bone, kidneys, and intestines. In the liver, ALP is concentrated in bile duct cells. Elevated ALP can come from the liver (bile duct obstruction, hepatitis) or bone (growth, Paget's disease, bone metastases). Comparing ALP with GGT helps determine the source: if both are elevated, the source is likely the liver.

Full Name
Alkaline Phosphatase (ALP)
Normal Range
44–147 U/L
Also Known As
Alkaline Phosphatase

Reference Range

LowNormal: 44–147 U/LHigh

Reference ranges may vary between laboratories, age groups, and sexes. The values shown are general adult reference ranges. Always compare your results to the specific range provided by your testing laboratory.

What Is ALP?

Alkaline phosphatase (ALP) is an enzyme found in several tissues, with the highest concentrations in the liver, bone, kidneys, and intestines. In the liver, ALP is concentrated in bile duct cells. Elevated ALP can come from the liver (bile duct obstruction, hepatitis) or bone (growth, Paget's disease, bone metastases). Comparing ALP with GGT helps determine the source: if both are elevated, the source is likely the liver.

Commonly included in:

Liver Function PanelBone PanelComprehensive Metabolic Panel

What Does High ALP Mean?

Above 147 U/L

Elevated ALP can indicate bile duct obstruction (gallstones, tumors), hepatitis, cirrhosis, bone diseases (Paget's disease, bone metastases, osteomalacia), hyperparathyroidism, or normal growth in children and adolescents. During pregnancy, the placenta produces ALP, causing normal elevation in the third trimester.

What Does Low ALP Mean?

Below 44 U/L

Low ALP is rare but can indicate hypophosphatasia (a genetic condition), zinc or magnesium deficiency, hypothyroidism, severe anemia, or malnutrition. Cardiac surgery patients sometimes have temporarily low ALP.

Related Biomarkers in Liver Function

ALT
Liver enzyme primarily found in liver cells — the most specific marker of liver damage.
Range: 0–41 U/L
AST
Enzyme found in liver, heart, and muscle — rises with tissue damage.
Range: 0–40 U/L
GGT
Liver enzyme particularly sensitive to alcohol consumption and bile duct obstruction.
Range: 0–55 U/L
Total Bilirubin
Yellow pigment from red blood cell breakdown processed by the liver.
Range: 0.1–1.2 mg/dL
Albumin
Most abundant blood protein, made by the liver, essential for fluid balance.
Range: 3.5–5.5 g/dL

Track Your ALP Over Time

Upload your blood test results to Hemoly and see how your ALP levels change over time. Get trend analysis, educational insights, and a personal health timeline.

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Medical Disclaimer

This information is for educational purposes only and is not intended as medical advice, diagnosis, or treatment. Reference ranges may vary between laboratories. Always consult a qualified healthcare professional for interpretation of your blood test results and before making any health decisions.