Colestyramine Amiodarone

ANION EXCHANGE RESINS ANTIARRHYTHMICS -AMIODARONE Colestyramine 1 amiodarone levels Colestyramine binds amiodarone, reducing its absorption and interrupting its enterohepatic circulation Avoid co-administration... 

A 62-year-old man took amiodarone for 2 years and developed hyperthyroidism carbimazole 40 mg/day, prednisolone, lithium, and colestyramine were ineffective and he died with hepatic encephalopathy and multiorgan failure. 

Colestyramine appears to reduce the serum levels of amiodarone. Clinical evidence... 

This interaction probably occurs because colestyramine binds with amiodarone in the gut, thereby reducing its absorption. It may also affect the enterohepatic recirculation of amiodarone. This is consistent with the way colestyramine interacts with other drugs. 

Information is very limited but a reduced response to amiodarone may be expected. Separating the dosages to avoid admixture in the gut would reduce or prevent any effects on absorption from the gut, but not the effects due to reduced enterohepatic recirculation. Monitor concurrent use closely and consider an alternative to colestyramine, or raise the amiodarone dosage if necessary. 

Nitsch J, Luderitz B. Beschleunigte elimination von Amiodaron durch Colestyramin. Dtsch MedWochenschr 9ZG) 111, 1241 4. 

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