amiodarone × hydrochlorothiazide

Same as the amiodarone/furosemide pair: thiazide-induced hypokalemia and hypomagnesemia raise amiodarone's arrhythmogenic potential. Additionally, both thiazides and amiodarone can cause hyponatremia.

Check potassium, magnesium, and sodium every 1–3 months. Keep potassium > 4.0 mmol/L. Obtain an ECG with QT measurement at baseline and every 6 months.