FXAB - Clinical: Xylose Absorption Test (Adult 25g dose)

Test Catalog

Test Name

Test ID: FXAB    
Xylose Absorption Test (Adult 25g dose)

Clinical Information Discusses physiology, pathophysiology, and general clinical aspects, as they relate to a laboratory test

Several drugs can interfere with test results






-MAO inhibitors

-Nalidixic acid


-Opium alkaloids


Reference Values Describes reference intervals and additional information for interpretation of test results. May include intervals based on age and sex when appropriate. Intervals are Mayo-derived, unless otherwise designated. If an interpretive report is provided, the reference value field will state this.

Serum fasting specimen: No reference intervals for the fasting serum: it is used as a blank when testing the two-hour specimen.


Serum xylose at 2 hours:

17 years and older:  32-58 mg/dL


Xylose excretion, % dose 5 hr:

17-64 years:   16-40 %

65 years and older:   14-40 %


Xylose excretion, g/5 hr:

17-64 years:   4.0-10.0 g/5hrs

65 years and older:   3.5-10.0 g/5hrs