D-Xylose absorption test measures D-Xylose level in the blood or urine sample. D- Xylose is a type of a sugar. The test helps to diagnose the problems with the small intestine which prevent small intestine from absorbing the nutrients in the food.

Usually D-Xylose is easily absorbed in the small intestine. In the absorption problem, D-Xylose is not absorbed in the intestine which results in low levels of D-Xylose in the blood and urine.

The D-Xylose test is done to diagnose if the symptoms such as chronic diarrhea, weakness, weight loss are due to the malabsorption. The person with the malabsorption cannot absorb nutrients, vitamins, and minerals from the intestinal tract into the blood stream. The test also checks why the child is not gaining the weight, especially when the child is eating too much of food.

If there is presence of the abnormally high bacteria amount in your intestine then you have to take antibiotics a day before the test. The test may lead you to dehydration. So drink enough fluids to replace the lost liquids after the test. In children younger than 12, the blood levels of D-Xylose are considered to be more reliable.

If you have kidney or bladder disease preventing you from emptying whole bladder then the test result may get affected. Physical activity during the test, conditions that result the food to remain for a long time in the stomach or some medicines like antibiotics and heart medicines can also affect the test results. There are no considerable risks in any blood or urine tests.