Gaviscon Advance Liquids Aniseed gets to work by forming a raft; over the contents of the stomach to prevent acid from leaving the stomach and refluxing back up the oesophagus (food pipe>. Gaviscon Advance contains double the concentration of sodium alginate of Gaviscon Original so forms a stronger, more resilient 'raft'. Ideal for long lasting relief from acid reflux as well as heartburn and indigestion. Gaviscon liquid does not contain sugar or gluten and can be taken during pregnant or breast-feeding. Gaviscon Advance liquids for heartburn and indigestion. Always read the label. Medicines can affect the unborn baby. Always talk to your doctor or pharmacist before taking any medicine during pregnancy. Please note that results may vary.