Comparative scintigraphic assessment of the intragastric distribution and residence of cholestyramine, Carbopol 934P and sucralfate

Formulation development of gastroretentive tablets of lamivudine using the floating-bioadhesive potential of optimized polymer blends

“…[65] The observed transit of the dosage form can then be correlated with the rate and extent of drug absorption. [66] Based on the results of in-vivo pharmacokinetic studies in rabbits, the optimized formulation was selected for g-scintigraphy studies in human volunteers owing to its better bioavailability potential. The optimized tablets, in all the subjects, were found to be either in the stomach or duodenum, even at 5 h sampling.…”

Decades of research in drug targeting to the upper gastrointestinal tract using gastroretention technologies: where do we stand?

“…In a study, similar time for 50% of particles to pass the pyloric sphincter was observed when cholestyramine powder was evaluated for the in vivo performance in humans using g-scintigraphy. The comparison of mucoadhesion was done using carbopol Õ 934P, a pHdependent polymer and sucralfate as a non-adhesive control (Jackson et al, 2001). In a study, erratic results were observed for gastroretention when microcrystalline Chitosan granules were evaluated by g scintigraphy for determination of mucoadhesion (Sakkinen et al, 2004).…”

IN VIVO IMAGING FOR VALIDATION OF ORAL DOSE PERFORMANCE

“…There are a variety of strategies that have been reported in order to achieve this, and imaging techniques have been intricately involved in the evaluation of their performance. Various studies have been performed on resins such as the anionic exchange resin cholestyramine and appear to show mucoadhesive properties with distribution and spread over the different sections of the stomach [62,63] and retention of at least 20% of the dose for up to 6 h [64,65]. These include confirmation of gastric retention of multiple unit alginate systems designed to circumvent the "all-ornothing" gastric emptying of unit dose formulations [58] and their further formulation development to include coadministration of citric acid solution as a means of further delaying gastric emptying [59].…”