How to prepare
No fasting is required. Drink water as normal.
This test is most useful when ordered alongside or after a standard liver function panel. If you have recent blood test results showing an elevated ALP, bring these to share with your practitioner when reviewing your isoenzymes result. A healthcare professional will take a blood sample from a vein in your arm.
After the test
Share your results with your GP or relevant specialist. If the liver fraction is elevated, your practitioner may arrange further liver or bile duct investigations. If the bone fraction is elevated, they may request imaging or markers of bone turnover such as parathyroid hormone (PTH) or vitamin D.
The result should always be interpreted alongside the full clinical picture.
Your test results will be available in your private dashboard. If there are any urgent issues, we'll let you know so you can follow up with your health professional.
Understanding results
Results report the proportion of ALP coming from the liver fraction and the bone fraction (and sometimes other sources such as intestinal or placental ALP). Reference ranges vary between laboratories.
A predominately elevated liver fraction points toward liver or bile duct conditions — such as cholestasis, bile duct obstruction, or liver infiltrative disease — as the likely source. A predominately elevated bone fraction suggests conditions causing increased bone turnover, such as Paget's disease, bone metastases, primary hyperparathyroidism, or healing fractures.
Your practitioner will review the isoenzyme breakdown alongside your total ALP, other liver markers, and clinical findings before making any recommendations.
