Gaviscon Extra Chewable tablets are flat, circular, bi-layer tablets with a peppermint flavour. Each tablet contains 250mg Sodium Alginate, 106.5mg Sodium Bicarbonate and 187.5mg Calcium Carbonate. This medicine is used for the treatment of acid related symptoms of gastro-oesophageal reflux such as acid regurgitation, heartburn and indigestion which may occur, for example, following meals or during pregnancy. They work in 2 ways: a combination of two antacids to neutralise excess stomach acid, and an alginate which forms a protective layer that floats on top of the stomach contents, keeping it away from the lining of the food pipe.