Reactions 1477, p18 - 9 Nov 2013

O SFlecainide

Poisoning in children: 2 case reportsA 35-month-old girl and a 3-year-old boy developed

flecainide poisoning following ’exploratory ingestion’ andoverdose due to a medication error, respectively.

The girl presented to an emergency department after an’exploratory ingestion’ of flecainide, with a maximumexposure of 75 mg/kg [amount ingested not clearly stated]. Shehad a history of paroxysmal supraventricular tachycardia, andhad been receiving propranolol and flecainide. Uponpresentation, she only responded to pain, and had a HR of74/min with wide-QRS, as well as a BP of 98/75 mm Hg withpoor perfusion [time to reactions onset not stated]. Shereceived sodium bicarbonate, sodium chloride, sodiumacetate and magnesium sulfate. Serial ECGs revealed gradualQRS narrowing. By 48 hours, she had fully recovered. At4 hours post-ingestion, her flecainide concentration was1.78 µg/mL.

The boy had a syncopal event and developed a wide-complex tachyarrhythmia. He had a history of supraventriculartachycardia, and had recently restarted flecainide. His parentshad been giving him a tenfold overdose of his prescribedflecainide [exact dosage, route and duration of overdose toreaction onset not stated]. He received sodium bicarbonateand magnesium sulfate, after which he reverted to sinusrhythm. One hour later, he had a short run ofhaemodynamically stable ventricular tachycardia, and hereceived sodium bicarbonate. His blood concentration offlecainide upon arrival at the emergency department had been2.03 µg/mL. Within 48 hours, his ECG normalised.

Author comment: "Our cases suggest the pediatricflecainide toxic syndrome may include central nervous systemdepression, syncope, QRS-interval widening, poor perfusion,and/or ventricular tachycardia."Marchese R, et al. Flecainide poisoning in two young children. Clinical Toxicology51: 599 abstr. 54, No. 7, Aug 2013. Available from: URL: http://dx.doi.org/10.3109/15563650.2013.817658 - USA 803095196

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Reactions 9 Nov 2013 No. 14770114-9954/13/1477-0001/$14.95 Adis © 2013 Springer International Publishing AG. All rights reserved