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

Abstract

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.

• Authors: Naoki Hiki, Michio Kaminishi, Kenjiro Yasuda, Noriya Uedo, Masumi Kobari, Terufumi Sakai, Takashi Hiratsuka, Kyota Ohno, Hajime Honjo, Sachiyo Nomura, Naohisa Yahagi, Hisao Tajiri, Hiroaki Suzuki
• Journal: Digestive endoscopy : official journal of the Japan Gastroenterological Endoscopy Society (Dig Endosc) Vol. 24 Issue 2 Pg. 79-86 (Mar 2012) ISSN: 1443-1661 [Electronic] Australia
• PMID: 22348831 (Publication Type: Clinical Trial, Phase II, Journal Article, Multicenter Study, Randomized Controlled Trial, Research Support, Non-U.S. Gov't)
• Copyright: © 2011 The Authors. Digestive Endoscopy © 2011 Japan Gastroenterological Endoscopy Society.

Chemical References

• Oils, Volatile
• Plant Oils
• Menthol
• peppermint oil

Topics

• Adult
• Aged
• Dose-Response Relationship, Drug
• Electrocardiography
• Endoscopy, Gastrointestinal
• Female
• Gastric Mucosa (drug effects, physiology)
• Humans
• Image Processing, Computer-Assisted
• Logistic Models
• Male
• Mentha piperita
• Menthol (administration & dosage, pharmacology)
• Middle Aged
• Oils, Volatile (pharmacology)
• Peristalsis (drug effects)
• Plant Oils (pharmacology)
• Young Adult