Sustained release liquid preparation using sodium alginate for eradicationof Helicobacter pylori

We prepared a new liquid preparation for eradication of Helicobacter pylori (HP), and examined drug release in vitro and in vivo. The liquid preparati on mainly consisted of a sodium alginate (AG) aqueous solution containing a mpicillin (ABPC), an antibiotic drug, or methylene blue, a dye, Drug releas e was retarded by Ca pre-treatment (0.10 M, 20 s) Of the AG preparation in in vitro drug release studies due to gel-formation at the liquid surface, I n in vitro experiments, the AG preparations were administered orally to rat s. The rats were divided into two groups,,vith or without pre-administratio n of ranitidine hydrochloride (RH, an H-2-blocker). The total remaining % o f ABPC in the stomach was high in the rats administered the AG preparation compared to the ABPC solution, The AG preparation might float in the stomac h without adhering to the gastric wall in the rats without pre-administrati on of RH, The total remaining % of ABPC at 30 min was almost 100% in the RH preadministration rats administered the AG preparation, and about 80% of t he drug existed in fraction 2 (implying adhesion of the preparation on the gastric mucus). At 60 min, the total remaining % in the AG preparation plus Ca (mean 87%) increased about 2-fold compared to that in the AG preparatio n alone (mean 44%), In this case, a large portion of the remaining ABPC als o existed in fraction 2, This preparation may be useful for eradication of HP.