Abstract
Ivabradine is currently approved to reduce heart rate in children with chronic heart failure and dilated cardiomyopathy. Ivabradine has also been used off-label in children to treat automatic tachyarrhythmias such as ectopic atrial tachycardia and junctional ectopic tachycardia. Adverse effects of ivabradine at physiological doses as well as its toxicity at supra-physiological doses have rarely been reported in adults. In children, weight-based dosing requires dilution of commercially available ivabradine oral solution for accuracy. We describe a case of ivabradine overdose in a newborn (treated for ectopic atrial tachycardia) secondary to inaccurate dosing leading to the infant receiving 10 times more drug than prescribed. This case highlights potential pitfalls of ivabradine prescription and preparation in children.