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.) The condition also includes spasms of the valve (lower esophageal sphincter) from the esophagus to the stomach, which prevents it from opening.

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 may occur at any age.

• difficulty swallowing liquids and solids
• regurgitation of food
• chest pain
  • increases after eating
  • may radiate to the back, neck, and arms
• weight loss
• heartburn
• cough

An upper GI and small bowel series shows absence of peristalsis and narrowing of lower 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.