Digoxin × Dronedarone

Dronedarone blocks intestinal P-glycoprotein – the main route of digoxin absorption and elimination. Digoxin plasma levels rise 1.7- to 2.5-fold. Dronedarone also enhances contractile and bradycardic effects.

Nausea, anorexia, visual disturbances (yellow-green halos around lights), arrhythmias ranging from premature beats to ventricular tachycardia. Older adults: confusion, dizziness. Symptoms appear within 1–2 weeks of co-administration.

When dronedarone starts, halve the digoxin dose; check level at 1 week. If sinus node or AV conduction symptoms appear, hold digoxin temporarily.