1999 Volume 22 Issue 1 Pages 55-60
We prepared a new liquid preparation for eradication of Helicobacter pylori (HP), and examined drug release in vitro and in vivo. The liquid preparation mainly consisted of a sodium alginate (AG) aqueous solution containing ampicillin (ABPC), an antibiotic drug, or methylene blue, a dye. Drug release 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. In in vivo experiments, the AG preparations were administered orally to rats. THe rats were divided into two groups, with or without pre-administration of ranitidine hydrochloride (RH, an H2-blocker). The total remaining % of 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 stomach without adhering to the gastric wall in the rats without pre-administration of RH. THe total remaining % of ABPC at 30 min was almost 100% in the RH pre-administration rats administered the AG preparation, and about 80% of the 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 preparation alone (mean 44%). In this case, a large portion of the remaining ABPC also existed in fraction 2. This preparation may be usuful for eradication of HP.