An evaluation of the antireflux properties of sodium alginate by means of combined multichannel intraluminal impedance and pH-metry.

Background: Alginate-based preparations act as mechanical antireflux barrier, which can reduce both acid and non-acid reflux events and limit the proximal migration of oesophageal refluxate. Aim: To evaluate all the above features with a novel technique, multichannel electrical impedance and pH-metry. Methods: Ten reflux patients underwent stationary impedancemetry and pH-metry after eating a refluxogenic meal. They were studied 1 h in basal conditions and 1 h after taking 10 mL of Gaviscon Advance. In both sessions, measurements were obtained in right lateral and supine decubitus. Results: Alginate preparation was able to decrease significantly (P < 0.05) the number of acid reflux events and the percentage time pH < 4.0 compared with baseline. There was no effect of the drug on non-acid refluxes. Gaviscon Advance was also significantly effective (P < 0.05) in reducing the height of proximal migration of reflux events compared with baseline in both decubitus positions. Conclusions: Our findings explain how Gaviscon Advance controls acid reflux episodes, limits the proximal migration of refluxed material and thereby decreases symptoms in clinical practice.