Citation

Fonck K, Haenebalcke C, Hemeryck A, Belpaire F, Jordaens L, Calle P, Buylaert W. J. Toxicol. Clin. Toxicol. 1998; 36(3): 247-251.

Affiliation

University Hospital of Ghent, Belgium.

Copyright

(Copyright © 1998, Marcel Dekker)

DOI

unavailable

PMID

9656983

Abstract

Case report: Propafenone is a class IC antiarrhythmic agent metabolized into two major metabolites, 5-hydroxypropafenone and N-depropylpropafenone. The potency of 5-hydroxypropafenone to block fast sodium channels is comparable to that of its parent. We report the positive correlation between plasma concentrations and electrocardiographic changes in a patient with severe oral self-poisoning. Serial ECG changes were measured and plasma concentrations were determined by high-performance liquid chromatography. The initial plasma concentrations of propafenone were in the toxic range and correlated with the widening of the QRS-complex. The slow decline in concentration during this first phase might relate to saturation of the isoenzyme CYP2D6. The half-life of propafenone, calculated from the second phase, was approximately 3 hours, defining the patient as a fast metabolizer. The initial concentrations of the metabolite N-depropylpropafenone were surprisingly higher than those of 5-hydroxypropafenone which may also be due to saturation of CYP2D6.

Language: en