The ratio of urine lactulose to urine L-rhamnose (L/R ratio) is a measure of intestinal permeability. Lactulose is a large molecule and normally very little is absorbed from the gut. Following a variety of insults the gut becomes more permeable, and lactulose may be absorbed into the blood from which it passes into the urine.

To read more or access our algorithms and calculators, please log in or register.