Sunday March 1, 2009


Q: In which clinical condition, usually a lower maintenance dose of warfarin is required?


Answer; In thyrotoxic atrial fibrillation

The recommended loading dose of warfarin in thyrotoxic atrial fibrillation is similar to euthyroid patients, but a lower maintenance dose is required because of accelerated clearance of vitamin K-dependent clotting factors.



Reference:

Shenfield GM. Influence of thyroid dysfunction on drug pharmacokinetics. Clin Pharmacokinet. 1981;6:275-297