ESOPHAGEAL ACID AND SALIVARY SECRETION - IS CHEWING GUM A TREATMENT OPTION FOR GASTROESOPHAGEAL REFLUX

The presence of acid in the oesophagus has been shown to stimulate sal ivary secretion, but the relevance of his oesophago-salivary reflex fo r acid clearance in physiological and pathological gastro-oesophageal reflux (GOR) is unknown. This study was designed to investigate the in terrelation between oesophageal acid and both resting and stimulated s alivary secretion. In 10 healthy volunteers, the acid clearance times after bolus infusion of 20 ml of 0.1 N hydrochloric acid were measured by means of ambulatory oesophageal pH monitoring. With a constant swa llowing rate and resting salivary flow, the acid clearance time was si gnificantly longer with dry as opposed to wet swallows (12.6 +/- 2.6 v s. 6.9 +/- 1.9 min; p = 0.01). When the salivary flow was doubled by c hewing a gum base (26.0 +/- 3.4 vs. 13.2 +/- 2.0 ml/15 min; p 0.005), the acid clearance time was markedly shortened (6.9 +/- 1.9 vs. 2.3 +/ - 0.2 min; p = 0.02). As compared with water control, salivary flow, p H, and protein content were not affected by a bolus infusion of hydroc hloric acid. This was true both for resting and gum-stimulated salivar y secretion. Our study suggests that an oesophago-salivary reflex beco mes effective only in prolonged episodes of GOR. This may explain why the water brash phenomenon is not regularly experienced by all reflux patients. Our study also suggests that chewing gum might be a non-phar macological treatment option for some patients with symptomatic GOR.