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

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.

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.

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.

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.

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.