Bezoars
A trapped mass of undigested material in the digestive tract
Quick Facts
- Type: Digestive (gastrointestinal) condition
- Main types: Hair, plant fiber, food, medication
- Usual location: Stomach
- Possible complication: Blockage of the digestive tract
Overview
A bezoar is a hard, compact mass of undigested material that collects in the digestive tract, most often the stomach. Over time, swallowed substances that the body cannot break down clump together and form a solid ball. Bezoars can range from small to large enough to fill much of the stomach.
They are named according to what they are made of. The main types are trichobezoars (hair), phytobezoars (plant fibers and indigestible food matter), pharmacobezoars (medications or supplements), and lactobezoars (milk, seen in some infants). Bezoars can cause symptoms by irritating the lining or by blocking the flow of food through the digestive tract.
Symptoms
Small bezoars may cause no symptoms. Larger ones often produce digestive complaints:
- Feeling full quickly when eating
- Loss of appetite and unintended weight loss
- Nausea and vomiting
- Abdominal pain or bloating
- A sensation of fullness or a lump in the upper belly
Warning signs of a complication include severe abdominal pain, persistent vomiting, inability to pass stool or gas, and vomiting blood. A bezoar that moves into the intestine can cause a blockage or, rarely, a perforation, both of which are emergencies.
Causes
Bezoars form when indigestible material accumulates faster than the stomach can clear it. Causes vary by type:
- Trichobezoars: Result from swallowing hair, usually in people who pull and eat their own hair.
- Phytobezoars: Form from fibrous plant matter, such as the skins and seeds of fruits and vegetables; persimmons are a well-known trigger.
- Pharmacobezoars: Build up from certain pills, supplements, or coatings.
- Lactobezoars: Occur in some infants from concentrated milk feeds.
Conditions that slow stomach emptying, such as gastroparesis or previous stomach surgery, make bezoars more likely.
Risk Factors
- Slow stomach emptying (gastroparesis), often from diabetes
- Previous stomach surgery
- A habit of pulling and eating hair (linked to pica or trichotillomania)
- Diets very high in fibrous, indigestible plant matter
- Reduced ability to chew food well
- Use of certain medications or supplements
Diagnosis
Bezoars are diagnosed using imaging and direct visualization:
- Upper endoscopy: A camera passed through the mouth lets the doctor see the bezoar directly, identify its type, and sometimes treat it.
- CT scan: Shows the mass and helps detect blockage or other complications.
- Upper GI series (barium study): X-rays after a contrast drink can outline the mass.
Doctors also look for underlying causes, such as slow stomach emptying or hair-eating behavior.
Treatment
Treatment depends on the size, type, and symptoms of the bezoar.
- Dissolving agents: Some phytobezoars can be broken down by drinking certain solutions, such as those containing cola or enzyme preparations, under medical supervision.
- Endoscopic removal: The bezoar may be broken apart and removed using instruments passed through an endoscope.
- Surgery: Large, hard, or hair bezoars that cannot be cleared, or those causing blockage or perforation, are removed surgically.
- Treating the cause: Managing slow stomach emptying and addressing hair-eating behavior helps prevent recurrence.
Prevention
- Manage conditions that slow stomach emptying, such as diabetes
- Chew food thoroughly and limit very fibrous, hard-to-digest foods if you are at risk
- Seek help for hair-pulling and hair-eating behaviors
- Follow dietary advice after stomach surgery
- Use medications and fiber supplements as directed
When to See a Doctor
See a doctor if you have ongoing nausea, vomiting, early fullness, or unexplained weight loss. Seek emergency care right away if you have:
- Severe abdominal pain or a swollen, hard belly
- Persistent vomiting or inability to keep food down
- Inability to pass stool or gas
- Vomiting blood or passing black or bloody stools
Frequently Asked Questions
What is a bezoar made of?
A bezoar is a hard mass of undigested material. Common types are made of hair (trichobezoar), fibrous plant matter and food (phytobezoar), medications or supplements (pharmacobezoar), or milk in infants (lactobezoar).
What are the symptoms of a bezoar?
Larger bezoars can cause early fullness, loss of appetite, nausea, vomiting, abdominal pain, and weight loss. Some cause no symptoms. Severe pain, persistent vomiting, or inability to pass stool may signal a blockage and needs urgent care.
Who is most likely to develop a bezoar?
People with slow stomach emptying (often from diabetes), those who have had stomach surgery, individuals who pull and eat their hair, and people eating very fibrous, hard-to-digest foods are at higher risk.
How are bezoars treated?
Treatment may involve dissolving the mass with special solutions, breaking it apart and removing it during an endoscopy, or surgery for large or hair bezoars. Doctors also treat any underlying cause to prevent it from returning.
Can a bezoar be dangerous?
Yes. A bezoar can block the digestive tract, cause ulcers, or rarely tear the wall (perforation), which are emergencies. Seek immediate care for severe abdominal pain, persistent vomiting, or no passage of stool or gas.
References
- MedlinePlus, U.S. National Library of Medicine. Bezoar.
- Mayo Clinic. Gastroparesis — Symptoms and causes.
- National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK). Gastroparesis.
- American Society for Gastrointestinal Endoscopy (ASGE). Gastric bezoars.