Intestinal absorption of 14C-labelled beta-cyclodextrin in rats.

: beta-Cyclodextrin and glucose labelled universally by 14C was administered orally to rats and blood radioactivity level was followed. In the case of glucose about 20% of the administered radioactivity, related to 10 ml blood was to be found and this appeared in the blood within 10 min following the oral administration. In the case of beta-cyclodextrin maximum 5% of the administered activity could be found in blood, and even this only 4 to 10 h following administration. Presumably, beta-cyclodextrin cannot be absorbed either from the stomach or from the small intestine, only the labelled open-chain dextrins and glucose formed from cyclodextrins on amylase action. Therefore it is very likely that the orally administered beta-cyclodextrin cannot provoke toxic symptoms.