The main abnormality in achalasia is a failure of the lower esophageal sphincter (a muscular ring at the junction of the esophagus and stomach) to relax during swallowing. The disorder is characterized by loss of the wave-like contraction of smooth muscles that forces food through the digestive tract. (These contractions are called peristalsis.)

Another part of the disorder is lack of nervous stimulation to the esophagus. Causes include damage to the nerves to the esophagus, parasitic infection, cancers, and hereditary factors. Achalasia is a rare disorder, may occur at any age, but is most common in middle-aged or older adults.

• Difficulty swallowing liquids and solids
• Regurgitation of food
• Chest pain which may increase after eating or may radiate to the back, neck, and arms
• Unintentional weight loss
• Heartburn
• Cough

An upper GI x-ray test or barium esophagogram may show absence of peristalsis, a dilated proximal esophagus, and a narrowing at the bottom of the esophagus. The diagnosis is confirmed with esophageal manometry. Physical examination may show signs of anemia.

The approach to treatment is to reduce the pressure at the lower esophageal sphincter. This may be achieved by manipulating the lower esophagus sphincter with special instruments.

Therapy usually involves dilation of the lower sphincter or injection with botulinum toxin to paralyze it and prevent spasms. Medications such as long-acting nitrates or calcium channel blockers can also be used to lower the pressure at the lower esophagus sphincter.

Surgery to decrease the pressure in the lower sphincter (called an esophagomyotomy) may be indicated if other interventions fail.

Surgical outcomes are good -- dilation alone often results in only temporary improvement in symptoms.

• Tearing (perforation) of the esophagus
• Regurgitation of acid or food from the stomach into the esophagus (reflux)
• Aspiration of food contents into the lung that can cause pneumonia

Many of the causes of achalasia are not preventable. However, treatment of the disorder may help to prevent complications.