In Zenker's diverticulum, a bulge or pouch forms at the top of the tube that connects the throat to the stomach, called the esophagus. The condition is not common. Connected bands of muscle that work to pass food from the mouth to the stomach make up the esophagus.

Over time, the bulge of Zenker's diverticulum can get bigger. Food, pills and even thick mucus can get stuck in the pouch instead of going through the esophagus. This can lead to problems with eating and other complications.

The cause of Zenker's diverticulum is not known. It happens most often to men older than 60. Treatment for symptoms of Zenker's diverticulum often is surgery.


A small Zenker's diverticulum may not have any symptoms. But the bulge may get bigger over time. It can trap food, mucus and pills. Symptoms might include:

  • Trouble swallowing, called dysphagia.
  • Burping.
  • A gurgling noise at the back of the throat.
  • Coughing.
  • Hoarseness.
  • Bad breath.
  • Choking.

If the pouch gets big enough, what's in it may spill into the throat. Then Zenker's diverticulum symptoms might include:

  • Feeling of food stuck in the throat.
  • Coughing up or spitting up food 1 to 2 hours after eating. This is called regurgitation.
  • Breathing food into the lungs, called aspirating.


The cause of Zenker's diverticulum isn't known. It's not known why the walls of the esophagus change to form a bulge or pouch in the condition.

The cause of Zenker's diverticulum might involve the muscles of the esophagus not working together. Most often, a muscle at the top of the esophagus relaxes to let the food down. If that doesn't happen, food can get trapped in the esophagus.

If the muscle in the area where the food gets trapped is weak, the food can cause the esophagus to bulge and form a pouch.

Risk factors

Risk factors for Zenker's diverticulum include:

  • Being older than 60.
  • Being male.
  • Having gastroesophageal reflux disease (GERD) or a condition in which part of the stomach bulges into the chest, called a hiatal hernia.
  • Having spinal surgery.


Complications can happen if Zenker's diverticulum isn't treated. The bulge of Zenker's diverticulum can get larger if it's not treated. Complications of Zenker's diverticulum can include:

  • Lung infection. Breathing in food, called aspirating, can lead to a lung infection. This is called aspiration pneumonia.
  • Weight loss and not getting enough nutrients, called malnutrition. Trouble swallowing can lead to weight loss and malnutrition.

June 18, 2024
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