Role of desethylamiodarone in the anticoagulant effect of concurrent amiodarone and warfarin therapy.

Article Details

Citation

Naganuma M, Shiga T, Nishikata K, Tsuchiya T, Kasanuki H, Fujii E

Role of desethylamiodarone in the anticoagulant effect of concurrent amiodarone and warfarin therapy.

J Cardiovasc Pharmacol Ther. 2001 Oct;6(4):363-7. doi: 10.1177/107424840100600405.

PubMed ID
11907638 [ View in PubMed
]
Abstract

BACKGROUND: The concurrent use of amiodarone and warfarin inhibits metabolism of S-warfarinby cytochrome P450 (CYP) 2C9, thereby increasing the anticoagulant effect of warfarin. Amiodarone primarily inhibits CYP1A2 and CYP3A4, and desethylamiodarone primarily inhibits CYP2C9. We investigate whether a relationship exists between the plasma concentration of desethylamiodarone and anticoagulation when amiodarone is administered to patients receiving warfarin therapy. METHODS AND RESULTS: The correlation between the plasma concentration of either amiodarone or desethylamiodarone, and prolongation of prothrombin time-international normalized ratio/dose of warfarin (Delta INR/Dose) on day 7 of amiodarone administration was studied in 25 patients (22-74 years old) with structural heart disease and refractory arrhythmias receiving stable warfarin therapy. RESULTS: No correlation was found between the plasma concentration of amiodarone and Delta INR/Dose, but a correlation was found between the plasma concentration of desethylamiodarone and Delta INR/Dose. CONCLUSIONS: It was suggested that inhibition of CYP2C9 by desethylamiodarone, the active metabolite of amiodarone, plays an important role in the interaction of warfarin and amiodarone.

DrugBank Data that Cites this Article

Drug Enzymes
DrugEnzymeKindOrganismPharmacological ActionActions
AmiodaroneCytochrome P450 1A2ProteinHumans
Unknown
Inhibitor
Details
AmiodaroneCytochrome P450 2C9ProteinHumans
Unknown
Inhibitor
Details