Baclofen-mediated gastro-oesophageal acid reflux control in patients with established reflux disease.

AIM: To explore the effect of baclofen on oesophageal acid exposure in patients with gastro-oesophageal reflux disease. METHODS AND MATERIALS: Twenty patients with established reflux disease were included in this double-blind, randomized, crossover study. Baclofen, 40 mg, or placebo was given as a single dose with a washout period of 4 weeks. Symptoms were assessed by a visual analogue scale. Oesophageal pH was registered for 12 h and analysed for the whole period and for the 0-4-h, 4-8-h, 8-12-h and 2-h post-prandial periods. RESULTS: Baclofen significantly reduced the number of reflux episodes during the 0-4-h (7.9 vs. 16.5, P < 0.0001; post-prandially: 6.0 vs. 11.2, P < 0.0001) and 0-12-h (46.5 vs. 73, P=0.0001; post-prandially: 18.8 vs. 29.3, P < 0.0001) periods. The fraction of time with pH < 4 was significantly lowered during the 0-4-h period (9.3 vs. 15.6, P=0.0019; post-prandially: 16.1 vs. 23.5, P=0.0083). Similar results were also obtained in patients with a hiatus hernia (n=13). Belching was significantly reduced (32 vs. 69 episodes, P < 0.01). CONCLUSIONS: A single oral dose of 40 mg baclofen significantly reduced both the number of reflux episodes and the fraction of time with pH < 4, an effect primarily found during the first 4 h after dosing.

24-H pharyngeal pH monitoring in healthy volunteers: a normative study.

BACKGROUND: Gastropharyngeal reflux has been associated with disorders of the upper and lower airways. It may be shown by pharyngeal pH-metry, but reports on normality in healthy volunteers are scarce. No definite consensus has been reached considering the upper limit of normality (ULN). The aim of the present study was therefore to quantify the occurrence of pharyngeal acid exposure (pH < 4) in healthy volunteers and, further, to examine its relation to acid exposure of the oesophagus and oesophageal motility and its occurrence in relation to age, sex, and body position. METHODS: Forty healthy volunteers underwent ambulatory 24-h pH-metry, using antimony electrodes positioned 2 cm above the upper oesophageal sphincter and 5 cm above the lower oesophageal sphincter on the basis of manometry. Technical artefacts were excluded before calculation of all results. RESULTS: Gastropharyngeal reflux occurred in most healthy volunteers without any significant relation to age, sex, or body weight. Pharyngeal acid reflux occurred mainly in the upright position. The ULN for pharyngeal acid exposure time was assessed to 0.9% (0.2% after exclusion of mealtimes). The ULN for the number of acid events in the pharynx was 18 (6.1). The corresponding ULNs for the oesophagus were 7% and 84. CONCLUSION: Gastropharyngeal reflux may be effectively monitored by ambulatory pH-metry. The present study provides reference limits, a prerequisite for evaluating the pathophysiologic importance of the phenomenon.