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At a Glance
Why Get Tested?
To evaluate for a possible liver disease or bile duct disease or to differentiate between liver and bone disease as a cause of elevated alkaline phosphatase (ALP); sometimes to screen for or monitor alcohol abuse
When to Get Tested?
When you have symptoms of a liver or bile duct disorder or as follow up when you have an increased ALP level
A blood sample drawn from a vein in your arm
Test Preparation Needed?
GGT levels fall after meals; you may be instructed to fast (nothing to eat or drink except water) for at least 8 hours prior to the test. You may also be asked to stop drinking alcohol or taking certain prescription medications.