Vomiting may be due to a variety of diseases, particularly in the upper gastrointestinal tract and these include gastric and duodenal ulcers and reflux oesaphagitis. Vomiting may also be a feature of gastro oesophageal reflux. If vomiting occurs soon after swallowing and consists of fresh food there may be obstruction in the oesophagus. Vomiting may also occur in the older population when dysmotility is present. It can occur when there is obstruction in the small intestine or the colon, the vomitus usually is bile stained and contains mucus and altered food. When the obstruction is lower down in the bowel there may be a smell suggesting faeces in the vomit. Medication is another cause of vomiting.