Thyrotoxicosis and CHF drugs - harry206

[ArchivalUser]

pt with thyrotoxicosis.
history of dilated cardiomyopathy and congestive heart failure
his medications include warfarin, digoxin, lisinopril, and carvedilol.

Which of the following changes in his therapeutic regimen should be made while he remains thyrotoxic?

A Decrease both warfarin and digoxin doses
B Increase both warfarin and digoxin doses
C Increase warfarin dose, decrease digoxin dose
D Decrease warfarin dose, increase digoxin dose
E No change in warfarin or digoxin dose

[ArchivalUser]

A? good conceptual question,

[ArchivalUser]

Tirotoxicosis cause steatorrea (Digoxin is not water soluble) so it would not be absorved...Hyperthyroid state increase sensibility to oral anticoagulants...Hypo states cause the oposite...example:

After achieving a euthyroid state with levothyroxine, the dose requirement of warfarin has to be decreased from 27 to 10 mg daily.

[ArchivalUser]

DD

[ArchivalUser]

Ans- D.

[ArchivalUser]

thanks harry.

[ArchivalUser]

Thanks Harry, would pls give some explanation for the answer.

[ArchivalUser]

The effect of thyrotoxicosis on warfarin dosing may seem counterintuitive. Although thyroid hormone increases the metabolism of warfarin, it increases the turnover of clotting proteins even more, resulting in a decreased dose requirement.

Digoxin metabolism is increased during thyrotoxicosis, so a dose increase can be anticipated.