The suppression of gastro-oesophageal reflux by alginates

The aim of this study was to compare alginate products with the same amount of active ingredients but different dosage forms, in the suppression of reflux provoked by a standard meal in healthy human volunteers, using ambulatory oesophageal pH monitoring.

This was a single centre, randomised, open, three-period crossover, controlled study comparing Gaviscon Advance (10 ml) with a control (10 ml water) and with a new tablet product containing the same active ingredients as Gaviscon Advance. Volunteers who had oesophageal pH < 4 for at least 2% of the 4-h period after ingestion of a test meal followed by control at a reflux screening visit were included in the study.

The difference between Gaviscon Advance and control in the mean angular transformed percentage of time for which oesophageal pH fell below four was statistically significant (p < 0.0001) demonstrating the sensitivity of the method. No significant difference between the two alginate products was found based on the least squares adjusted mean angular transformed percentage of time for which pH fell below four. There were also no significant differences between the two alginate dosage forms in the angular transformed percentage of time for which oesophageal pH fell below five and in the log-transformed number of occasions on which oesophageal pH fell below four and five.

The study shows that alginate reflux suppressants containing a low amount of antacid are effective in suppressing acid reflux and that suspension and tablet forms are able to give equivalent acid suppression.