indication

Used to lower high cholesterol levels in the blood.

pharmacology

Dextrothyroxine, the dextrorotary isomer of the synthetic thyroxine, is a antihyperlipidemic.

mechanism of action

Dextrothyroxine is a antihyperlipidemic. The mechanism of action is not completely understood, but dextrothyroxine apparently acts in the liver to stimulate formation of low-density lipoprotein (LDL) and, to a much greater extent, to increase catabolism of LDL. This leads to increased excretion of cholesterol and bile acids via the biliary route into the feces, with a resulting reduction in serum cholesterol and LDL. Dextrothyroxine has no significant effect on high-density lipoproteins (HDL). Inherently, it will also bind to thyroid receptors and as it is a prohormone, it will bind as a substrate to iodide peroxidase.

toxicity

Symptoms of dextrothyroxine overdose are unknown.

drug interactions

Acenocoumarol: The thyroid hormone, dextrothyroxine, increase the anticoagulant effect of acenocoumarol.

Anisindione: The thyroid hormone, dextrothyroxine, increase the anticoagulant effect of anisindione.

Dicumarol: The thyroid hormone, dextrothyroxine, increase the anticoagulant effect of dicumarol.

Digoxin: The thyroid hormone, dextrothyroxine, decreases the effect of digoxin.

Warfarin: The thyroid hormone, dextrothyroxine, increase the anticoagulant effect of warfarin.