<p>The mode of action of the product is physical and does not depend on absorption into the systemic circulation. On ingestion, the product reacts rapidly with gastric acid to form a raft of Alginic acid gel having a near-neutral pH and which floats on the stomach contents quickly and effectively impeding gastro-esophageal reflux, for up to 4 hours. In severe cases, the raft itself may be refluxed into the esophagus in preference to the stomach contents and exert a demulcent effect.</p>