Gastroesophageal reflux-induced diseases are among the most common disorders and are associated with classical oesophageal manifestations of gastroesophageal reflux disease (GERD) including a range of symptoms such as heartburn, acid regurgitation and chest pain, and also organic manifestations such as oesophagitis, oesophageal strictures and ulcerations, Barrett's oesophagus and oesophageal adenocarcinoma. Recognition of its impact on other organ systems, extra-oesophageal reflux diseases, such as the ear, nose and throat (ENT) region and the bronchopulmonary system, as well as its contribution to symptoms such as chest pain and sleep disturbances, is also increasing. This paper addresses the symptoms, diseases and complications in which the abnormal reflux of gastric content to the oesophagus and adjacent organ systems is believed to be a frequent contributory factor.