Gastrointestinal transit of a drug-resinate administered as an oral suspension

Abstract The distribution in the gastrointestinal tract of a radiolabelled drug-resinate formulation, administered in the form of an oral suspension, and the concomitantly administered water wash, was investigated using the technique of dual-isotope gamma scintigraphy. The results demonstrate the influence of the suspension formulation on the gastric emptying and small intestinal transit properties of the drug-resinate complex. Emptying of the suspension formulations from the stomach was independent of the concomitantly administered water wash. In all cases, emptying of the suspension from the stomach was slower than that of the water wash. The distribution of the labelled resinate in the stomach, and subsequent gastric emptying, was influenced by the physical characteristics of the suspension. Although the study was only carried out in a small number of subjects, the small intestinal transit of the non-aqueous suspensions formulated using Migylol was significantly shorter than that of the aqueous suspensions. This may be due to the inclusion of certain pharmaceutical excipients in the formulations. Further work is required to investigate the possibility that these excipients may act as small intestinal cathartics.