Oral Sustained Release Drug Delivery System Using Polymer Film Composites

Abstract

Of the several possible routes of introduction of sustained release medication into the body the oral administration of single dose medicinals is one of the simplest and safest since it does not pose a sterility problem and the risk of damage at the site of administration is minimal. Ordinarily, however, an oral sustained release (SR) formulation is subjected to frequently changing environments during transit through the gastro-intestinal tract as it passes from the strongly acidic to the weakly alkaline medium in the lower part of the small intestine. The variable absorbing surfaces over the length of the GI tract adds further constraint to the design of oral dosage forms. Moreover, the stomach emptying time varies from patient to patient. These factors combine to introduce considerable variability in the performance of oral SR systems. In order to overcome these disadvantages, the dosage form of this work was designed so as to be retained in the stomach for prolonged periods of time and to release most of the active agent under the controlled conditions therein at a steady rate. Several approaches have been taken in the past to prolong the retention of the dosage form in the stomach (1,2,3). This paper describes a flexible, sustained release polymer-drug delivery composite film device for oral administration which could be dispensed and administered in a compact form which extends in the stomach to remain buoyant. The film was suitably marked for facile measurement of prescribed medical dosage according to length.