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.