ABSORPTION ENHANCEMENT OF DEXTRAN SULFATE AFTER ENTERAL ADMINISTRATION IN A DISPERSION

Dextran sulfate sodium, a polyanion with a relative molecular mass of approximately 8000, is poorly absorbed after oral or enteral administr ation of aqueous solutions. When given to rats without absorption enha ncers, no drug was found in serum using an analytical method with a de tection limit of 0.08 mu g/ml. Delivery of the drug in a dispersion fo rmulation containing 10 mM monoolein and 20 mM sodium taurocholate inc reased the absorption of dextran sulfate from the small intestine of r ats. Drug was present in serum after administration of the formulation locally to the duodenum, jejunum and the ileum. The ileum was selecte d for further study. Data from 12 rats showed variability in the maxim um drug concentration and the time at which it occurred. Negligible ab sorption enhancement occurred when the formulation was given orally by gavage. When intestinal contents were present, absorption was reduced Direct administration of the formulation to the absorptive site produ ced significant blood levels of the drug. This indicates intestinal ab sorption enhancement of dextran sulfate can be achieved.