Pharmacobezoar

https://www.ncbi.nlm...pubmed/30808405
J Med Case Rep. 2019 Feb 27;13(1):45. doi: 10.1186/s13256-019-1984-0.
Endoscopic removal of a gastric pharmacobezoar induced by clomipramine, lorazepam, and domperidone overdose: a case report.
Abstract
INTRODUCTION:
Gastric pharmacobezoars are a rare entity that can induce mechanical gastric outlet obstructions and sometimes prolong toxic pharmacological effects. Certain medications, such as sustained-release forms, contain cellulose derivatives that may contribute to the adhesion between pills and lead to the creation of an aggregate resulting in a pharmacobezoar. Case reports are rare, and official guidelines are needed to help medical teams choose proper treatment options.
CASE PRESENTATION:
Our patient was a 40-year-old Caucasian woman with borderline personality disorder and active suicidal thoughts who was found unconscious after a massive drug consumption of slow-release clomipramine, lorazepam, and domperidone. On her arrival in the emergency room, endotracheal intubation was preformed to protect her airway, and a chest x-ray revealed multiple coffee grain-sized opaque masses in the stomach. She was treated with activated charcoal followed by two endoscopic gastric decontaminations 12 h apart in order to extract a massive gastric pharmacobezoar by manual removal of the tablets.
CONCLUSION:
This case demonstrates that in the case of a massive drug consumption, a pharmacobezoar should be suspected, particularly when cellulose-coated pills are ingested. Severe poisoning due to delayed drug release from the gastric aggregate is a potential complication. Detection by x-ray is crucial, and treatment is centered on removal of the aggregate. The technique of decontamination varies among experts, and no formal recommendations exist to date. It seems reasonable that endoscopic evaluation should be performed in order to determine the appropriate technique of decontamination. Care should be patient-oriented and take into account the clinical presentation and any organ failure, and it should not be determined solely by the suspected medication ingested. Thus, serum levels are not sufficient to guide management of tricyclic antidepressant intoxication.

https://www.ncbi.nlm...pubmed/30306811
Clin Toxicol (Phila). 2019 Apr;57(4):271-281. doi: 10.1080/15563650.2018.1513138. Epub 2018 Oct 11.
Potential pharmacobezoar formation of large size extended-release tablets and their dissolution - an in vitro study.
Abstract
OBJECTIVE:
Extended release (ER) tablets/capsules in massive ingestion overdoses are prone to form pharmacobezoars potentially increasing the risk of late-appearing toxic effects and prolonged symptoms. Oral activated charcoal is often sufficient to prevent drug absorption, but in a recent massive ingestion of highly toxic substances, prior orogastric lavage might be considered. The disintegration characteristics of ER preparations in overdose situations is valuable to understand if the time line and course of the intoxication might be prolonged, but information on these characteristics are unavailable. Slow disintegration and/or pharmacobezoar formation, and the large size makes ER preparation impossible to evacuate using a 30F orogastric lavage tube. This study evaluates the disintegration and pharmacobezoar formation of a simulated massive ER tablet ingestion in an in vitro model, using a selection of extended release tablets, with different disintegrating characteristics when present in therapeutic numbers. Furthermore, the sizes of the formed pharmacobezoars were compared with the dimensions of a 30F orogastric lavage tube.
METHOD:
A standardized model mimicking the physical effects on pharmaceutical preparations in simulated gastric fluid (SGF) was developed and tested on three mono-depot ER tablets (quetiapine/Seroquel®XR 50 mg, paracetamol/Pinex®Retard 500 mg, verapamil/Isoptin®Retard 240 mg), one poly-depot ER tablet (carbamazepine/Tegretol®Retard 200 mg), and one immediate-release tablet (paracetamol/Panodil® 500mg). Thirty tablets were placed in polyamide mesh bags, either together in one bag or in separate bags, immersed in 1 L SGF, and incubated at 37 °C for 48 h. Released drugs were quantified at 0.5-48 h.
RESULTS:
Visual inspection showed that Seroquel®XR, Pinex®Retard, and Isoptin®Retard tablets formed firm pharmacobezoars stable for more than 4 h and intact fractions remained for up to 24 h. Drug releases were reduced by 53%, 40%, and 31%, respectively, for up to 8 h compared to separated tablets. Light microscopy showed that contact with SGF transformed the coating of Seroquel®XR and Pinex®Retard to a diffusion-controlled swelled gel-layer, and the Isoptin®Retard tablets into a rigid and slow-releasing matrix. Tegretol®Retard disintegrated into microspheres within 30 min, and Panodil® disintegrated within minutes.
DISCUSSION:
The developed pharmacobezoars of mono-depot ER tablets demonstrated prolonged drug release. Neither the formed pharmacobezoars, nor the single tablets of the tested mono-depot ER preparations, would pass through the lumen of a standard orogastric lavage tube, rendering this modality ineffective for tablet removal in gastrointestinal decontamination.