Block of HERG Potassium Channels by the Antihistamine Astemizole and its Metabolites Desmethylastemizole and Norastemizole
@article{Zhou1999BlockOH, title={Block of HERG Potassium Channels by the Antihistamine Astemizole and its Metabolites Desmethylastemizole and Norastemizole}, author={Z Zhou and Vicken R. Vorperian and Qiuming Gong and S Zhang and Craig T. January}, journal={Journal of Cardiovascular Electrophysiology}, year={1999}, volume={10} }
Electrophysiologic Effects of Astemizole Metabolites. Introduction: The selective H1‐receptor antagonist astemizole (Hismanal) causes acquired long QT syndrome. Astemizole blocks the rapidly activating delayed rectifier K+ current IKr and the human ether‐a go‐go‐related gene (HKRG) K+ channels that underlie it. Astemizole also is rapidly metabolized. The principal metabolite is desmethylastemizole, which retains H1‐receptor antagonist properties, has a long elimination time of 9 to 13 days, and…
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