D-xylose test

Purpose

To investigate absorption in the small intestine after the oral administration of D-xylose, a pentose sugar which is absorbed in the duodenum and the upper jejunum but which is not metabolised in the body.

Subject preparation

Fasting for 12 hours and at rest.

Product

Xylose

Protocol

Samples

• After centrifugation, draw off the plasma and store at +4°C.

Assays

• Xylose in the blood.

Contraindications

Do not carry out if the subject has diarrhoea, kidney or liver failure, or a bacterial infection.

Comment

Results are invalid if the subject vomited or ate anything during the challenge. Drinking water is allowed.