Dronedarone, a derivative of
amiodarone with similar mechanisms of action (blocking calcium, potassium and
sodium channels in addition to having anti-adrenergic effects) does not contain
iodine and has shown no thyroid toxicity in its clinical trials, has fewer drug
interactions than amiodarone, and has rare if any proven pulmonary toxicity.1-8 Very rarely, dronedarone has produced severe
hepatic failure – not shown predictable by routine hepatic function test
monitoring in its clinical trials (see the package insert for details). Dronedarone’s effects on blocking the L-type
calcium current are dose/concentration dependent and require higher levels than
its effects on the sodium channel and on potassium channels.1 (and,
Belardinalli and Zeng, 2012 personal communication) Dronedarone is approved for the treatment of
atrial fibrillation (see below); has had limited studies for other arrhythmias;
and has no adverse drug-ICD interactions reported.
Credits: James A. Reiffel, MD