The influence of the route of administration on the bioavailability of an endogenous macromolecule: chondroitin sulphate (CSA).

The absorption of chondroitin sulphate (CSA) has been investigated in rabbits after the oral administration of a single dose of 100 mg of CSA per kg of body weight. The oral dose was administered as a lipid suspension or in enteric capsules. No absorption of CSA could be demonstrated. Oral administration did not cause the release of a clearing factor into the bloodstream, a phenomenon that is known to occur in the presence of CSA. The concentration of this factor did not decrease after oral administration of CSA.