Multicenter phase II randomized study evaluating dose-response of antiperistaltic effect of L-menthol sprayed onto the gastric mucosa for upper gastrointestinal endoscopy.

AIM: Peppermint oil solution was found to be effective for reducing gastric spasm during upper gastrointestinal endoscopy. The aim of the present study was to assess whether the gastric peristalsis-suppressing effect is dose-dependently induced by L-menthol, the major constituent of peppermint oil, and to determine the recommended dose of an L-menthol preparation. METHODS: In this phase II, multicenter, double-blind, dose-response study, 131 eligible patients were randomly assigned to receive 20 mL of 0.4% L-menthol (n = 32), 0.8% L-menthol (n = 35), 1.6% L-menthol (n = 30), or placebo (n = 34). The primary efficacy measure was the proportion of subjects with no peristalsis in two time periods, 75 to 105 s after treatment and immediately before the completion of endoscopy. RESULTS: The peristalsis-suppressing effect of L-menthol increased dose dependently (5.6%, 32.0%, 47.4% and 52.9% in the 0%, 0.4%, 0.8% and 1.6% groups, respectively: P < 0.001, one-tailed Cochran-Armitage trend test). As compared with the placebo group, the proportion of subjects with no peristalsis after administration was significantly higher in the 0.8% group (P = 0.015) and 1.6% group (P = 0.009). Adverse events in the L-menthol dose groups occurred with similar frequencies in the placebo group. CONCLUSION: L-menthol suppresses peristalsis in a dose-dependent manner, and the dose-response reaches a plateau at 0.8% L-menthol. Further Phase III studies are needed to establish the superiority of 0.8% L-menthol over placebo.

Reduction in salivary cortisol level by music therapy during colonoscopic examination.

BACKGROUND/AIMS: Premedication for endoscopy promotes patient cooperation and makes subsequent examinations more acceptable. Music therapy is widely used in the treatment of acute and chronic pain. Therefore, we investigated the effects of music therapy on pain and on salivary cortisol levels in patients undergoing screening colonoscopy. METHODOLOGY: The subjects were 29 consecutive patients undergoing colonoscopy for various reasons. Patients were randomly assigned to undergo colonoscopy while listening to music (n=15) or while not listening to music (n=14). Cortisol levels were measured in samples of saliva obtained before and after colonoscopy. After colonoscopy, patients were asked to rate their maximum pain during colonoscopy. RESULTS: Patients who listened to music during colonoscopy tended to have lower pain scores. Salivary cortisol levels increased significantly less in the group receiving music. CONCLUSIONS: Music therapy during colonoscopy markedly reduces fear-related stress, as indicated by changes in salivary cortisol levels.

Suppression by iron chelator phenanthroline of sodium chloride-enhanced gastric carcinogenesis induced by N-methyl-N'-nitro-N-nitrosoguanidine in Wistar rats.

The effect of prolonged administration of iron chelator phenanthroline on sodium chloride-enhanced gastric carcinogenesis induced by N-methyl-N'-nitro-N-nitrosoguanidine, and the labeling and apoptotic indices in the gastric cancers was investigated in Wistar rats. After 25 weeks of carcinogen treatment, the rats were given chow pellets containing 10% sodium chloride and intraperitoneal injections of phenanthroline at doses of 15 or 30 mg/kg body weight every other day. At week 52, feeding of sodium chloride significantly increased the incidence of gastric cancers, as compared with the control group. Prolonged injections of phenanthroline at both doses significantly reduced the incidence of gastric cancers, which was enhanced by oral supplementation with sodium chloride. Phenanthroline at both doses significantly decreased the labeling index of gastric cancers, which was enhanced by sodium chloride, and significantly increased the apoptotic index of gastric cancers, which was lowered by sodium chloride. In vitro examination using electron spin resonance revealed that sodium chloride promotes the production of hydroxyl radical during Fe(2+) oxidation by Fenton's reaction. These findings suggest that enhancement by sodium chloride of gastric carcinogenesis may be mediated by hydroxyl radicals.