The tube that carries food from the mouth to the stomach is the esophagus or food pipe. Achalasia makes it harder for the esophagus to move food into the stomach.
There is a muscular ring at the point where the esophagus and stomach meet. It is called the lower esophageal sphincter (LES). Normally, this muscle relaxes when you swallow to allow food to pass into the stomach. In people with achalasia, it does not relax as it should. In addition, the normal muscle activity of the esophagus (peristalsis) is reduced or absent.
This problem is caused by damage to the nerves of the esophagus.
Other problems can cause similar symptoms, such as cancer of the esophagus or upper stomach, and a parasite infection that causes Chagas disease.
Achalasia is rare. It may occur at any age, but is most common in people ages 25 to 60. In some people, the problem may be inherited.