Gaviscon medicines treat heartburn and indigestion. They contain alginates, which form a protective layer on top of the stomach contents to help keep acid from rising into the food pipe.We stock Gaviscon Advance Aniseed liquid, Gaviscon Peppermint liquid, Extra Strength chewable tablets in 24 and 48 packs, and Gaviscon Infant sachets. Always read the label. Ask our pharmacist before giving Gaviscon Infant to a baby. See your GP if you have heartburn most days for three weeks or more, or if it comes with difficulty swallowing, vomiting or weight loss you cannot explain. Browse digestive health.