Bupropion overdose: insights on the role of upper gastrointestinal decontamination endoscopy.

INTRODUCTION: Although bupropion is known to be associated with pharmacobezoar formation, it remains understudied in this context. Upper gastrointestinal endoscopy has emerged as a potential adjunctive decontamination technique for managing acute overdoses associated with pharmacobezoar formation. We aim to evaluate its role in acute bupropion overdoses.

METHODS: We retrospectively analysed intentional bupropion overdoses referred to the Pavia Poison Control Centre (2015-2024) in which upper endoscopy was performed. Data on patient characteristics, overdose details, co-ingestants, decontamination procedures, endoscopy indications, and findings were collected. Endoscopy outcomes were classified as positive (pharmacobezoars, intact tablets, or paste-like residues) or negative. In parallel, an in vitro model was used to assess the propensity of bupropion to form pharmacobezoars.

RESULTS: Forty-seven patients were included (median age 44 years, IQR 27-55; 75% female). The median ingested bupropion dose was 4,500 mg (IQR 4,500-6,750 mg). The median ingested tablets count was 59 (IQR 29-100 mg), and co-ingestants were present in 79% of cases. Upper gastrointestinal decontamination endoscopy was positive in 28 cases (60%). Pharmacobezoars or tablet residues were identified even in patients who had undergone prior decontamination, including orogastric lavage (60%). The only variable significantly associated with positive endoscopic findings was the total number of ingested tablets (P <0.05). In our cohort, nearly three-quarters of patients ingesting ≥30 tablets showed a substantial rate of positive endoscopy 73%, compared to 33% of those ingesting <30 tablets. All positive cases resulted in successful endoscopic removal without complications. The in vitro experiment showed early pharmacobezoar formation within four hours of incubation, persisting for up to 72 hours.

DISCUSSION: Acute bupropion overdoses, alone or with co-ingestants, can cause gastric pharmacobezoars and retained tablets/residues despite standard decontamination. Upper gastrointestinal decontamination endoscopy is effective early post-ingestion and may complement or replace conventional methods.

CONCLUSIONS: Gastric pharmacobezoars and tablet residues are frequently observed in bupropion overdoses, particularly with ingestions of ≥30 tablets, making these patients potential candidates for early endoscopic removal.