Background: The management and toxicokinetics of hydroxychloroquine overdose are poorly described.
Case report: We report a case of an 18-year-old girl who ingested 20 g of hydroxychloroquine. She developed marked hypokalemia, hypotension, and ventricular tachyarrhythmias but survived with treatment including intubation, adrenaline infusion, high-dose diazepam, and aggressive potassium replacement. Plasma hydroxychloroquine level was 29.40 mumol/L (9.87 mg/L) 2 hours after ingestion and the elimination half-life of hydroxychloroquine was 22 hours.
Conclusions: The clinical manifestations of this hydroxychloroquine overdose were similar to those reported for chloroquine overdose and the management principles recommended for chloroquine overdose appeared to be efficacious in this case.