[Pilot study on clinical effects of rebamipide gargle against oral mucositis induced by fluoropyrimidines].

Rebamipide, a cytoprotective agent, has been suspected to attenuate oral mucositis through anti-inflammatory potentials and induction of endogenous prostaglandin synthesis. This prospective study was designed to assess the clinical efficacy of rebamipide gargle against oral mucositis, which is induced by fluoropyrimidines in patients with stomach and colorectal cancer. We first conducted a pilot study on gargle flavors, because the solution in this agent has a strong and bitter after taste. Nine kinds of flavors were prepared, and six characteristics were evaluated by ten volunteers: sourness, bitterness, sweetness, remain, after taste, and hard to drink. We determined the contents of rebamipide using HPLC, which showed stability in an acidic condition. Finally, we decided that 100% Pokka Lemon should be used as the flavor of the rebamipide solution. A clinical study was then started to compare the preventive effects rebamipide gargle and placebo have on stomatitis, quality of life (QOL), and the therapeutic effects of chemotherapy.

Effect of chitosan on gastrointestinal absorption of water-insoluble drugs following oral administration in rats.

Chitosan is widely used as a dietary weight-loss supplement in Japan. In the present study, we examined the effect of chitosan on the gastrointestinal absorption profiles of the water-insoluble drugs, indomethacin and griseofulvin, and the water-soluble drugs, acetaminophen and cephalexin, after oral administration in rats. Rats received oral administration of chitosan (5 mg/kg or 25 mg/kg) dissolved in 5% acetic acid or vehicle 15 min before oral administration of each drug. Chitosan at a dose of 25 mg/kg, but not 5 mg/kg, significantly decreased the plasma concentrations of indomethacin and griseofulvin after administration as a suspension with a significant delay of the time to reach maximum concentration compared to the corresponding control values (vehicle-pretreated rats). However, pretreatment of chitosan (25 mg/kg) did not change the pharmacokinetics of indomethacin administered as a solution. Further, the same dose of chitosan had no effect on the pharmacokinetics of acetaminophen. The gastrointestinal absorption profile of an amino-beta-lactam antibiotic, cephalexin, which is actively absorbed via carrier-mediated transport system, was also unchanged. The present findings at least suggest the possibility that chitosan at high dose reduces the gastrointestinal absorption of water-insoluble drugs such as indomethacin and griseofulvin, but not water-soluble drugs, by diminishing the surfactant-like effect of bile acids.