Diagnostic drug, diagnostic method and diagnostic device for permeability of intestinal mucosa

A diagnostic method, comprising:

• orally administering or enema administering chitin and/or chitosan that is not labeled with FITC to a test subject;
• measuring a concentration of the chitin and/or chitosan in blood of the test subject to which the chitin and/or chitosan are orally administered or enema administered, after a lapse of a predetermined period of time;
• and
• evaluating a degree of leaky gut syndrome of the test subject based on the measured concentration of the chitin and/or chitosan in the blood as compared to a concentration of chitin and/or chitosan in blood of a control which does not have leaky gut syndrome and to which the chitin and/or chitosan are orally administered or enema administered.

A food and drink evaluation method, comprising:

• allowing a test subject to eat and drink a single or a plurality of specific foods and drinks;
• allowing the test subject to orally ingest chitin and/or chitosan that is not labeled with FITC during the eating and drinking, or before or after the eating and drinking;
• measuring a first concentration of the chitin and/or chitosan in blood of the test subject collected after a lapse of a first predetermined period of time from the oral ingestion;
• measuring a second concentration of the chitin and/or chitosan in blood of the test subject collected after a lapse of a second predetermined period of time from the oral ingestion, the second predetermined period of time is later than the first predetermined period of time;
• and
• determining whether the single or plurality of specific foods and drinks have a potential to serve as a factor increasing or decreasing permeability of intestinal mucosa of the test subject based on the measured first concentration of the chitin and/or chitosan in the blood and the measured second concentration of the chitin and/or chitosan in the blood.

An evaluation method, comprising:

• administering a given substance to a test subject;
• separately orally administering or enema administering chitin and/or chitosan that is not labeled with FITC to the test subject;
• measuring blood concentrations of the chitin and/or chitosan in blood of the test subject before and after the administration of the given substance;
• and
• evaluating whether the given substance has a normalizing action on permeability of intestinal mucosa, and how strong the normalizing action, when present, is, based on the measured concentration of the chitin and/or chitosan in the blood of the test subject after the administration of the given substance as compared to the measured concentration of the chitin and/or chitosan in the blood of the test subject before the administration of the given substance.