Alkaline Phosphatase
Disclaimer: Information on this page is for educational purposes. Consult a physician to interpret your test results. Lissa Health helps track biomarker trends but does not replace medical advice.
What This Test Measures
Alkaline phosphatase (ALP) is found in liver, bone, intestine, and placenta. Elevation may reflect cholestasis or increased bone turnover.
When ALP is elevated, isoforms (bone vs liver) or concurrent GGT help differentiate the source.
ALP is physiologically elevated in children and adolescents due to bone growth.
Normal Ranges
| Group | Reference Range |
|---|---|
| Men | 40–130 U/L |
| Women | 35–105 U/L |
| Children | Up to 390 U/L (age-dependent) |
Reference ranges may vary by laboratory and assay method.
Causes of High Levels
- Cholestasis and obstructive jaundice
- Paget disease, bone metastases
- Growth in children
- Pregnancy
- Hyperparathyroidism
Causes of Low Levels
- Hypothyroidism
- Zinc deficiency
- Malnutrition
- Hypophosphatasia (rare)
Test Preparation
- Fasting preferred
- Report pregnancy and bone pain
Related Biomarkers
| Biomarker | Relationship |
|---|---|
| Gamma-Glutamyl Transferase (GGT) | Hepatic ALP source |
| Direct Bilirubin | Cholestasis |
| Calcium | Bone metabolism |
FAQ
How often should I take this test?
With cholestasis — every 1–3 months; with bone disease — as directed.
What should I do if my result is abnormal?
Isolated elevation — bone/liver isoforms and imaging if needed.
Last updated: June 2026