A bezoar is a mass often found trapped in the gastrointestinal system, though it can occur in other locations. A pseudobezoar is an indigestible object introduced intentionally into the digestive system.There are several varieties of bezoar, some of which have inorganic constituents and others organic. The term has both a modern (medical, scientific) and traditional usage. Types
By content
Food boluses (or boli; singular bolus) have the archaic and positive meaning of bezoar, and are composed of loose aggregates of food items such as seeds, fruit pith, or pits, as well as other types of items such as shellac, bubble gum, soil, and concretions of some medications. Lactobezoars are a specific type of food bezoar comprising inspissated milk. It is most commonly seen in premature infants receiving formula foods. Pharmacobezoars (or medication bezoars) are mostly tablets or semiliquid masses of drugs, normally found following overdose of sustained-release medications. Phytobezoars are composed of indigestible plant material (e.g., cellulose), and are frequently reported in patients with impaired digestion and decreased gastric motility. Diospyrobezoar is a type of phytobezoar formed from unripe persimmons. Coca-Cola has been used to treat them. Trichobezoar is a bezoar formed from hair – an extreme form of hairball. Humans who frequently consume hair sometimes require these to be removed. In cases of Rapunzel syndrome, surgery may be required. By location
A bezoar in the esophagus is common in young children and in horses; in horses, it is known as choke. A bezoar in the large intestine is known as a fecalith.
A cook in the Kings court was sentenced to death, and chose to be poisoned. Paré administered the bezoar stone to the cook, but it had no effect, and the cook died in agony seven hours after taking the poison, proving that contrary to popular belief, the bezoar could not cure all poisons.Modern examinations of the properties of bezoars by Gustaf Arrhenius and Andrew A. Benson of the Scripps Institution of Oceanography show that when bezoars are immersed in an arsenic-laced solution, they can remove the poison. The toxic compounds in arsenic are arsenate and arsenite; each is acted upon differently by the bezoars: arsenate is removed by being exchanged for phosphate in brushite found in the stones, while arsenite is bound to sulfur compounds in the protein of degraded hair, which is a key component in bezoars.A famous case in the common law of England (Chandelor v Lopus, 79 Eng Rep. 3, Cro. Jac. 4, Eng. Ct. Exch. 1603) announced the rule of caveat emptor ("let the buyer beware") if the goods they purchased are not in fact genuine and effective. The case concerned a purchaser who sued for the return of the purchase price of an allegedly fraudulent bezoar.