Self-administered pentobarbitone overdose with prolonged coma and delayed toxicological diagnosis

Pentobarbitone is a short-acting barbiturate central nervous system depressant used primarily for veterinary anaesthesia and euthanasia. Pentobarbitone has recognised clinical uses, including in anaesthesia and management of refractory seizures but may also be encountered in cases of intentional overdose. This report presents the case of a patient who ingested pentobarbitone and required mechanical ventilation for 6 days. Pentobarbitone and a barbiturate test kit were later found in the patient's home. Blood analysis revealed pentobarbitone concentrations of 91, 56 and 19 mg/L at 11, 59 and 107 hours post-ingestion, respectively. Following intensive supportive care, the patient made a full recovery. The case describes coma, respiratory failure and barbiturate-associated skin and vascular complications, with diagnosis delayed due to the agent's absence from standard hospital drug screens. As pentobarbitone may not cross-react with common phenobarbitone assays, rapid access to comprehensive toxicological analysis is critical for identifying uncommon toxicities and guiding timely clinical and public health responses. This case highlights that pentobarbitone toxicity may mimic severe neurological injury and may not be detected on routine hospital toxicology screening.