How reports print it
ALPЩФЩелочная фосфатазаФосфатаза щелочнаяФосфатаза щелочная общаяЩелочная фосфатаза общаяALKPAlkaline phosphatase
What it shows
An enzyme of the liver, bile ducts and bones.
Units and conversion
Base unit: U/L.
- 1 µkat/L = 60 U/L · 1 U/L = 0.01667 µkat/L
Enzyme activity depends on the method and the measuring temperature, so it is not converted between methods. Converting 1 µkat/L = 60 U/L only changes the unit.
Typical ranges
Your laboratory’s range comes first — it is printed on the report next to the result. Below is one laboratory’s adult range with its method: a reference, not a rule.
| Who | Range, U/L |
|---|---|
| Men, 18–19 years | 55–149 |
| Women, 18–19 years | 45–87 |
| Men, 20 years and older | 40–130 |
| Women, 20 years and older | 35–105 |
Range source: Лаборатория Хеликс — Фосфатаза щелочная общая
Good to know
For adults over 19, Helix gives 35–105 U/L for women and 40–130 U/L for men; teenagers have higher ranges.
Why it can be higher
Common reasons discussed with a doctor. This is not a diagnosis.
- Bone growth in teenagers — so their ranges are higher
- Pregnancy: the placenta makes it too
- Bile flow problems
- Bone conditions and fracture healing
Why it can be lower
- A low alkaline phosphatase is rare; a doctor looks for the reason
What to ask a doctor
- Does the rise come from the liver or from bone?
- Is GGT needed for comparison?
Whom to see
A GP or internist.