Metolazone in Heart Failure and Hypertension Management

Introduction to Metolazone

The American College of Cardiology recommends loop diuretics as the preferred first-line diuretic agents for most patients with heart failure, with metolazone reserved for patients who do not respond adequately to moderate or high-dose loop diuretics 1, 2
The combination of metolazone with a loop diuretic produces a synergistic effect that can overcome diuretic resistance in refractory cases, as recommended by the American College of Cardiology 2, 4

The American College of Cardiology recommends an initial daily dose of metolazone of 2.5 mg once daily, with a maximum total daily dose of 20 mg, and a duration of action of approximately 12-24 hours 1, 5

The American College of Cardiology notes that the addition of metolazone to loop diuretics significantly increases the risk of electrolyte abnormalities, requiring close monitoring for hypokalemia, hyponatremia, hypochloremia, and metabolic alkalosis 1, 2

The 2022 AHA/ACC/HFSA guidelines give a Class 1, Level B-NR recommendation for adding metolazone to loop diuretics in patients with heart failure who don't respond to moderate or high-dose loop diuretics, as stated by the American College of Cardiology 1, 2
The American College of Cardiology suggests considering metolazone as an option in patients with hypertension and concomitant mild fluid retention 2