BLOOD TEST · SMART CARE POLYCLINIC, DEIRA
Alkaline Phosphatase explained
An enzyme from the bile ducts and from bone. A rise points to one or the other.
What the Alkaline Phosphatase test measures
An enzyme with two main sources: the lining of the bile ducts in the liver, and bone. A third, the placenta, matters in pregnancy. Because bone is a source, a raised result is not automatically about the liver — which is where it is worked up from.1
Reported as part of Liver Function Test.
What the result tells you
Raised out of proportion to ALT
Suggests bile flow is obstructed rather than that liver cells are damaged — a different problem from the one ALT reports.
How liver and bone are separated
By adding a GGT, which rises with the liver source and not the bone one. Raised ALP with a normal GGT sends the question towards bone.
Raised and entirely normal
Children and teenagers growing quickly run high because their bones are active, and it rises late in pregnancy from the placenta.
From bone
Healing fractures, vitamin D deficiency and conditions of bone turnover — which is why it sits beside calcium, phosphate and vitamin D.
How to prepare
- Fasting
- Not needed, but usually taken with a fasting panel
- Best time
- Morning, with the rest of the panel
- Worth knowing
- A fatty meal shortly beforehand can raise it slightly in some people.
What can move the result
A result outside the usual range does not on its own mean something is wrong. These are the everyday explanations a doctor considers first.
Frequently asked questions
An enzyme with two main sources: the lining of the bile ducts in the liver, and bone. A third, the placenta, matters in pregnancy. Because bone is a source, a raised result is not automatically about the liver — which is where it is worked up from. Raised out of proportion to ALT: Suggests bile flow is obstructed rather than that liver cells are damaged — a different problem from the one ALT reports.
Fasting: Not needed, but usually taken with a fasting panel. Best time: Morning, with the rest of the panel. A fatty meal shortly beforehand can raise it slightly in some people.
Commonly: obstruction to bile flow, including gallstones; bone growth in children and teenagers, which is normal; the third trimester of pregnancy; vitamin D deficiency and other bone conditions; some medicines, including certain antibiotics. A single result is not a diagnosis. Values are read against the laboratory's own reference range and alongside your history, your symptoms and the rest of the panel — which is why every package includes a doctor to go through them with you.
At Smart Care Polyclinic, 29 Doha Centre, Al Maktoum Rd, Deira, Dubai. Walk in during opening hours or call +971 (0)4 379 3562.
Sources
Written from current guidance and reviewed 31 August 2026.
Sources cited above
- Kwo PY, Cohen SM, Lim JK. ACG Clinical Guideline: Evaluation of Abnormal Liver Chemistries. The American Journal of Gastroenterology. 2017;112(1):18-35. PMID 27995906. doi:10.1038/ajg.2016.517The American College of Gastroenterology guideline on what a raised liver enzyme actually means and how an abnormal result should be worked up.
Sources are listed for the specific statements they support. They are published research and guidance, not a substitute for a consultation — what applies to you is decided by a doctor who has assessed you.
- ALP (alkaline phosphatase) testMedlinePlus, US National Library of Medicine
- Evaluation of abnormal liver chemistriesAmerican Association for the Study of Liver Diseases
- Liver function testNHS