BACKGROUND Atropine, an anticholinergic agent with central and peripheral actions, reduces gastro-oesophageal reflux (GOR) in normal subjects and patients with gastro-oesophageal reflux disease (GORD) by inhibiting the frequency of transient lower oesophageal sphincter relaxation (TLOSR).

AIMS To compare the effect of methscopolamine bromide (MSB), a peripherally acting anticholinergic agent, with atropine on the rate and mechanism of GOR in patients with GORD.

RESULTS Atropine significantly reduced basal LOS pressure (12.6 (0.17) mm Hg to 7.9 (0.17) mm Hg), and the number of TLOSR (8.1 (0.56) to 2.8 (0.55)) and reflux episodes (7.0 (0.63) to 2.0 (0.43)) (p<0.005 for all comparisons). MSB reduced basal LOS pressure (12.6 (0.17) to 8.7 (0.15) mm Hg, p<0.005), but had no effect on the frequency of TLOSR (8.1 (0.56) to 7.5 (0.59)) and reflux episodes (7.0 (0.63) to 4.9 (0.60)) (p>0.05).

CONCLUSION In contrast to atropine, MSB has no effect on the rate of TLOSR or GOR in patients with GORD. Atropine induced inhibition of TLOSR and GOR is most likely mediated through a central cholinergic blockade.