Pharmacobezoar: An Evolving New Entity

Abstract

Pharmacobezoars, bezoars comprised of medications, are unusual entities. Medications reported to cause bezoars include aluminum hydroxide gel, enteric-coated aspirin, sucralfate, guar gum, cholestyramine, enteral feeding formulas, psyllium preparations, nifedipine XL, and meprobamate. They most often occur, as do bezoars of any type, in a background of altered motility or anatomy of the gastrointestinal tract. Bowel hypoactivity, dehydration, and concomitant use of anticholinergics and narcotis appear to contribute to the propensity for bezoar formation by aluminum hydroxide gel and Isocal. The hygroscopic properties of psyllium and guar gum appear to contribute to their propensity to form bezoars. Insolubility of the carrying vehicle of enteric-coated aspirin and nifedipine is the setting in which these medications form bezoars. In contrast to nonmedication bezoars, pharmacobezoars may produce additional symptoms, those related to the release of their active ingredients. In patients with suspected gastrointestinal tract emptying problems, whether esophageal, gastric, small bowel, or colonic, the astute clinician should consider pharmacobezoar in the differential diagnosis.

Emergency Department Management of the Salicylate-Poisoned Patient

“…The ototoxicity is most noticeable in the range of serum salicylate from 20 to 40 mg/dL [40,42]. Aspirin, especially enteric-coated formulations, are known to develop concretions and bezoars in the stomach and act as a direct GI irritant leading to nausea, vomiting, and abdominal pain [22,43,44].…”

Letter to the Editor: Protective Effect of Medication Bezoar After a Massive Beta-Blocker, Digoxin, and Amitriptyline Poisoning

“…Medications reported to cause bezoars include aluminium hydroxide gel, sucralfate, nifedipine, meprobamate cholestyramine, or amitriptyline (1,2). In the present case, the bezoar formation avoided significant severe side effect after a potential lethal poisoning with beta-blocker, digitalis, and amitriptyline.…”

“…Bowel hypoactivity, dehydration, and concomitant use of anticholinergic and narcotics may contribute to the ability to form bezoars (2). In the present case, amitriptyline's atropinic side effects on the gut can be the causal factor for this bezoar formation (4).…”

MDCT imaging of the stomach: advances and applications

“…The risk factors for the formation of gastric bezoar include gastric dysmotility from prior gastric surgery or vagotomy, gastric outlet obstruction, dehydration, use of opiates (or other gastroparetic medications) and use of medications with insoluble carrying vehicles like enteric-coated aspirin. 47 Bezoars are usually detected incidentally in patients undergoing work-up for non-specific symptoms. CT typically shows the presence of an intraluminal mass with typical mottled air lucencies within (Figure 15a).…”