Antiperistaltic Effect and Safety of L-menthol and Placebo for Upper GI Endoscopy in the Elderly With Contraindication to Buscopan: a Prospective, Randomized, Double-blind Study

Endoscopy is a important tool for diagnosis and treatment of gastrointestinal diseases. Effective inhibition of gastrointestinal motility during examination is important to achieve good results and quality.

Traditionally, hyoscine-N-butylbromide (Buscopan) is the most commonly used drugs that inhibit intestinal peristalsis. But the side effects of drugs were mentioned in many studies, such as arrhythmia, increased glaucoma, dysuria in patients who have benign prostatic hypertrophy and allergic reactions, and may even cause anaphylactic shock. Peppermint oil is the extract of the natural plant (Mentha X piperita L) which was growth in North America and Europe. L-menthol is main component of peppermint oil. In animal experiments, peppermint oil had effect of calcium channel blockers and cause gastrointestinal smooth muscle relaxing effect. Clinically, peppermint oil preparations were used to relieve stress headache, non-ulcer dyspepsia and irritable bowel syndrome. The oral or intestinal local spraying of peppermint oil or L-menthol showed inhibition of intestinal peristalsis in many studies, and improved colonoscopy, barium enema, retrograde cholangiography , and upper gastrointestinal endoscopy examination.

With the aging of the population of Taiwan and the universality of endoscopy for elderly patients, the safety of endoscopy in elderly patients has more and more attention. According to ASGA guidelines, age is not a contraindication for endoscopy. But 50% of elderly patients have contraindications for hyoscine-N-butylbromide use. Therefore, effort to find alternative medicine to improve quality of endoscopy in elderly patients is necessary. Therefore, the investigators design a research for comparing effect and safety of L-menthol and placebo in elderly patients who have contraindication of hyoscine-N-butylbromide.