Definition and epidemiology
A bezoar is a concretion of accumulated, undigested foreign material that forms within the gastrointestinal lumen, almost always in the stomach, though fragments can migrate distally.
- Phytobezoar: composed of plant fibers, skins, and seeds; the most common type overall, especially after gastric surgery (altered motility, reduced acid, pyloroplasty/vagotomy) or in diabetics with gastroparesis.
- Trichobezoar: composed of hair, almost exclusively seen in young women/girls with trichotillomania (hair pulling) and trichophagia (hair eating), often with an underlying psychiatric disorder.
- Pharmacobezoar: aggregation of medications, particularly sustained-release or enteric-coated tablets, or drugs with hygroscopic/binding properties (e.g., bulk laxatives, antacids, sucralfate).
- Lactobezoar: curdled milk/formula mass seen in premature or low-birth-weight infants fed concentrated formula.
Bezoars are uncommon overall but are an important cause of gastric outlet obstruction and small bowel obstruction in specific populations (post-surgical stomach, diabetic gastroparesis, psychiatric trichotillomania).
- Trichobezoar classically occurs in young women with trichotillomania and trichophagia
- Rapunzel syndrome = trichobezoar extending from stomach into small bowel
- Phytobezoars are most common after gastric surgery (vagotomy, pyloroplasty, Billroth II) or in diabetic gastroparesis
- Persimmons are a classic phytobezoar-causing food due to tannins
- CT shows a heterogeneous, non-enhancing, mottled intraluminal mass
- Succussion splash and palpable epigastric mass are classic trichobezoar exam findings
- Endoscopy is both diagnostic and often therapeutic
- Large or hair-based bezoars often require surgical gastrotomy rather than endoscopic removal alone
Etiology and risk factors
- Prior gastric surgery (Billroth II, vagotomy, pyloroplasty, bariatric surgery) altering gastric emptying and acid output
- Diabetic gastroparesis and other causes of delayed gastric emptying
- Trichotillomania and trichophagia, more common in adolescent and young adult females, often linked to anxiety, developmental delay, or other psychiatric comorbidity
- Poor dentition or inadequate chewing, especially in elderly patients eating fibrous foods (persimmons, celery, coconut)
- Hypothyroidism and other causes of reduced gastric motility
- Excessive ingestion of persimmons (high in tannins that polymerize and form a gelatinous mass) is a classically cited phytobezoar cause
- Polypharmacy with sustained-release formulations or medications that form concretions
Pathophysiology
Normal gastric motility and acid secretion grind and digest most ingested material, which then passes through the pylorus. When material resists digestion (hair, high-tannin plant fiber, certain drug matrices) or when gastric emptying is impaired (post-surgical anatomy, gastroparesis, reduced acid), undigested fragments accumulate and mat together, forming a cohesive mass.
Trichobezoars form because hair is not digestible and its smooth, scale-like surface promotes layering within gastric folds; the mass can enlarge over months to years, taking the shape of the stomach and sometimes extending through the pylorus into the duodenum and jejunum (Rapunzel syndrome).
The resulting mass can cause local mucosal pressure necrosis, ulceration, and bleeding, and can mechanically obstruct the gastric outlet or small bowel, leading to obstruction, perforation, or intussusception in severe cases.
Clinical features
- Early satiety, postprandial fullness, nausea, and vomiting
- Epigastric pain or discomfort
- Weight loss and anorexia in chronic cases
- Palpable, mobile, non-tender epigastric mass (classic for trichobezoar)
- Succussion splash on auscultation with movement
- Halitosis in some trichobezoar cases
- Signs of anemia or occult GI bleeding from mucosal ulceration
- Alopecia (patchy hair loss) in patients with trichotillomania
- Acute presentation with bowel obstruction (distension, obstipation, bilious vomiting) if the bezoar migrates distally
Diagnosis
Diagnosis combines history, physical exam, imaging, and endoscopy.
Initial evaluation
- History should screen for prior gastric surgery, diabetes, hypothyroidism, dietary habits, medication use, and hair-pulling/eating behaviors
- Physical exam for epigastric mass and signs of obstruction
Imaging
- Plain abdominal radiograph may show a mottled gastric mass but is often nonspecific
- Barium upper GI series classically shows a mobile intragastric filling defect with a mottled, speckled appearance
- CT abdomen is the most useful modality, showing a well-defined, heterogeneous intraluminal mass with a characteristic mottled or whorled appearance, without contrast enhancement; CT also assesses for obstruction and extent of extension
Endoscopy
- Upper endoscopy is both diagnostic and often therapeutic, allowing direct visualization, biopsy if needed, and attempted fragmentation/removal
| Modality | Typical finding |
|---|---|
| Plain film | Mottled gastric soft-tissue mass |
| Barium study | Mobile filling defect, speckled pattern |
| CT | Heterogeneous, non-enhancing intraluminal mass |
| Endoscopy | Direct visualization and tissue sampling |
Differential diagnosis
- Gastric malignancy (adenocarcinoma, GIST, lymphoma) — mass lesion but typically enhances and infiltrates wall
- Gastric outlet obstruction from peptic ulcer disease
- Gastroparesis without bezoar formation
- Foreign body ingestion (single object rather than matted mass)
- Small bowel obstruction from adhesions, hernia, or tumor when the bezoar has migrated distally
- Intussusception in pediatric patients
- Pyloric stenosis in infants (for lactobezoar presentations)
Management
Management depends on bezoar type, size, location, and presence of complications; guideline consensus favors a stepwise approach from least to most invasive.
Phytobezoar
- Enzymatic dissolution with cellulase or papain-containing agents, and prokinetic agents such as metoclopramide to promote gastric emptying, can be first-line for uncomplicated cases
- Endoscopic fragmentation and removal (mechanical disruption, retrieval, or combined with chemical dissolution) if medical therapy fails
- Carbonated beverages (e.g., cola) as adjunct therapy for soft phytobezoars have supportive evidence and are sometimes used before endoscopy
Trichobezoar
- Endoscopic removal is often difficult due to size and density of hair; surgical removal (gastrotomy) is frequently required, especially for large trichobezoars or Rapunzel syndrome
- Psychiatric referral for trichotillomania/trichophagia is essential to prevent recurrence; behavioral therapy (habit-reversal training) and selective serotonin reuptake inhibitors (fluoxetine, sertraline) may be used for underlying impulse-control or obsessive-compulsive spectrum features
Pharmacobezoar
- Supportive care, discontinuation of offending agent, endoscopic removal if obstructive; monitor for drug toxicity from ongoing dissolution
- N-acetylcysteine is sometimes used off-label as a mucolytic agent to help dissolve certain pharmacobezoars
Lactobezoar
- Usually self-limited: temporary cessation of feeds, hydration, and formula dilution; rarely needs intervention
Surgery
- Indicated for large bezoars unresponsive to endoscopic therapy, Rapunzel syndrome, perforation, or bowel obstruction
Follow-up endoscopy to confirm resolution is reasonable in high-risk patients (e.g., recurrent trichobezoar).
Complications and prognosis
- Gastric ulceration and gastrointestinal bleeding from chronic mucosal pressure
- Gastric outlet obstruction
- Small bowel obstruction or intussusception from bezoar fragments (Rapunzel syndrome)
- Perforation and peritonitis, which carry significant morbidity and mortality if untreated
- Pancreatitis or biliary obstruction rarely, from mass effect
- Prognosis is generally good with timely removal; trichobezoar recurrence is common without psychiatric treatment of the underlying trichotillomania
- Mortality is low overall but increases substantially with perforation or missed Rapunzel syndrome
BEZOAR: Bulimia/behavioral (trichotillomania), Enzymes (cellulase/papain) for phytobezoar, Zero/reduced gastric acid (acid suppression, prior surgery) impairs digestion of fibrous material, Obstruction is the key complication, Age/sex (young females for trich-, post-gastric-surgery for phyto-), Removal via endoscopy or surgery.
Practice questions
1. A 16-year-old girl presents with early satiety, epigastric fullness, and a palpable nontender mass in the left upper quadrant. On exam, she has patchy areas of hair loss on the scalp. Which of the following is the most likely diagnosis?
2. A 68-year-old man with a history of Billroth II gastrectomy for peptic ulcer disease presents with postprandial fullness and vomiting after eating persimmons. CT shows a heterogeneous, non-enhancing mass in the gastric lumen. What is the most appropriate initial management?
3. A 19-year-old woman with a known trichobezoar undergoes endoscopy, which fails to remove the mass due to its large size and density. Imaging shows the hair mass extending from the stomach through the pylorus into the proximal jejunum. Which of the following best describes this finding and the next best step?
Frequently asked questions
What causes a bezoar?
A bezoar forms when indigestible material, such as hair, plant fiber, or medication residue, accumulates in the stomach instead of passing through normally. Risk factors include prior gastric surgery, diabetic gastroparesis, trichotillomania with hair-eating, poor dentition, and ingestion of high-tannin foods like persimmons. Reduced gastric motility or acid secretion allows these materials to mat together into a persistent mass.
What are the first symptoms of a bezoar?
Early symptoms are usually nonspecific: early satiety, postprandial fullness, nausea, mild epigastric discomfort, and sometimes a vague sense of abdominal mass. As the bezoar enlarges, patients may develop weight loss, vomiting, and a palpable epigastric mass. Trichobezoar patients may also have visible patchy hair loss from trichotillomania.
How is a bezoar diagnosed?
Diagnosis is based on history (prior gastric surgery, hair-pulling behavior, diet), physical exam for an epigastric mass, and imaging. CT is the most useful imaging test, showing a characteristic heterogeneous, non-enhancing, mottled mass within the gastric lumen. Upper endoscopy confirms the diagnosis directly and is often used for treatment at the same time.
Is a bezoar curable?
Yes, bezoars are generally curable with removal, either through enzymatic dissolution, endoscopic fragmentation, or surgery for large or complicated cases. Phytobezoars often respond well to medical and endoscopic therapy. Trichobezoars tend to recur unless the underlying trichotillomania and trichophagia are treated with psychiatric or behavioral therapy.
Trichobezoar vs phytobezoar — what is the difference?
A trichobezoar is composed of swallowed hair and occurs almost exclusively in young women or girls with trichotillomania and trichophagia, often requiring surgical removal due to its density. A phytobezoar is composed of plant fibers and skins, more common in patients with altered gastric motility after surgery or in diabetics, and often responds to enzymatic dissolution or endoscopic therapy without surgery.
Key drugs
Related conditions and differentials
Sources and further reading
StatPearls (NCBI Bookshelf)MedlinePlusWHO ICD-10: T18
Educational content for medical students, prepared by the WhiteCoat Pro editorial team with AI assistance; every page is reviewed by a second AI model for factual errors. It is not medical advice and does not replace the product label, local guidelines or a clinician.