The most common sign of narrowing is a sensation of a lump in the foodpipe, especially after swallowing. When the foodpipe narrows, swallowing becomes more difficult and uncomfortable, resulting in a lack of appetite and, in some cases, vomiting. Other signs include pain or pressure in the chest, neck, or back when swallowing or coughing; persistent heartburn; weight loss; changes in taste or smell; and trouble breathing. A doctor can diagnose an esophageal blockage by performing a physical examination and testing your blood pressure during swallowing exercises to see how much it drops. There are two types of esophageal blocks: mechanical and chemical. With mechanical obstruction, food gets stuck at the level of the esophagus where the muscle attaches to the skull. This may be caused by a tumor or other disease process. With chemical obstruction, excess acid from stomach or pancreas juices causes swelling and inflammation of the esophagus, which results in food sticking to the lining of the esophagus. Most often, both mechanisms are involved. Blockages can be temporary or permanent. If you think you may have an esophageal block, seek medical help immediately. The first thing your doctor will do is perform a thorough medical history and physical examination.