Journal of Clinical Toxicology
Open Access

Abstract

Massive Valproic Acid Overdose with Confirmed Pharmacobezoar Formation and Neuromuscular Toxicity: A Case Report and Literature Review

Maryam Alrazooqi*, Lara Abumuaileq, Sania Zia and Sara Nooruddin Kazim

Introduction: We present the case of a 42-year-old male who arrived obtunded to our Emergency Department (ED) following an intentional ingestion of approximately 60 grams of extended-release Valproic Acid (VPA). Subsequent imaging and endoscopy confirmed the presence of a pharmacobezoar, a rare and underreported complication of overdose, and his course was further distinguished by the development of delayed neuromuscular toxicity. Methodology: Clinical, laboratory, imaging, endoscopic and neurophysiologic data were abstracted from the electronic medical record. Case Report: The patient was managed with early airway protection, gastrointestinal decontamination initially with single-dose and later with multiple-dose activated charcoal regimens. He received Intravenous (IV) Levocarnitine (L-carnitine), naloxone and Continuous Renal Replacement Therapy (CRRT). His hospital course was initially stable but later complicated by delayed neuromuscular toxicity with extrapyramidal features requiring prolonged inpatient rehabilitation and multidisciplinary follow-up including toxicology, intensive care, psychiatry, internal medicine and neurology teams. Discussion: This case highlights the clinical challenge of massive VPA overdose complicated by pharmacobezoar formation and delayed neuromuscular sequelae. Early risk assessment led to recognition and aggressive treatment of a potentially life-threatening ingestion in which airway protection, serial monitoring, endoscopic confirmation and extracorporeal elimination were crucial to a favourable outcome. Literature review shows that while delayed absorption and toxicity are well described in sustained-release formulations, few reports have confirmed bezoar formation endoscopically and neuromuscular toxicity after acute overdose remains rare. The combination of an endoscopically confirmed pharmacobezoar with subsequent neurological sequelae makes this case distinctive and adds to the growing literature. Conclusion: This case emphasises the importance of anticipating pharmacobezoar formation in sustainedrelease VPA overdoses and recognising that delayed neuromuscular syndromes may emerge even after initial stabilisation. Clinicians should consider early toxicology involvement, advanced imaging and endoscopy in such cases. Aggressive gastrointestinal decontamination, L-carnitine therapy and timely extracorporeal removal remain mainstays of care. Ultimately, ongoing vigilance and coordinated multidisciplinary follow-up are essential.

Published Date: 2025-10-31; Received Date: 2025-10-01