Effect of hyoscine N-butylbromide on gastroesophageal reflux in normal subjects and patients with gastroesophageal reflux disease

OBJECTIVES: Recent studies have shown that atropine reduces gastroesophagea l reflux in normal subjects and patients with gastroesophageal reflux. The aim of the study has been to assess the effects of an atropine derivative, hyoscine N-butylbromide in normal subjects and patients with gastroesophage al reflux disease by recording esophageal and gastric pH-metry for a 24-h p eriod. METHODS: Ten normal subjects and 10 patients with gastroesophageal reflux d isease were evaluated. PH-metry was performed using two glass pH flexible p robes with distal incorporated electrodes. The two catheters were introduce d nasally under fluoroscopy. One probe was positioned in the gastric body; the other was placed 5 cm above the lower esophageal sphincter which had be en evaluated manometrically before the study. Recording lasted without inte rruption for 48 h. Patients and normal subjects were assigned to receive hy oscine N-butylbromide (10 mg p.o.t.i.d.) for 24 h followed by a placebo for another 24 h or vice versa in a random manner. The pH was analyzed for a t otal number of acid refluxes and percentage of the period with pH <4 in the esophagus and the mean gastric pH in 24 h. before and after treatment with hyoscine N-butylbromide. RESULTS: The number of reflux episodes was significantly greater with hyosc ine N-butylbromide in comparison with a placebo in patients with gastroesop hageal reflux disease and normal subjects (p < 0.02). The percentage of tim e with pH <4, was also significantly greater in patients with gastroesophag eal reflux disease and in controls (p < 0.05). The mean 24-h gastric pH aft er hyoscine N-butylbromide was not different from placebo in gastroesophage al reflux disease and controls. CONCLUSIONS: Hyoscine N-butylbromide. an anticholinergic agent, increases t he total number of esophageal acid refluxes in patients with gastroesophage al reflux disease and in controls. therefore it is not recommended in the t reatment of gastroesophageal reflux disease. (C) 2001 bv Am. Coll. of Gastr oenterology.