Diuretic resistance is common among patients with acute decompensated heart failure, and one strategy for overcoming this phenomenon is sequential nephron blockade with loop plus thiazide-type diuretics. Metolazone is an oral thiazide-type diuretic commonly used for this purpose. Due to its delayed absorption, some clinicians suggest that metolazone be given 30-60 minutes prior to the loop diuretic. However, the efficacy and safety of such a strategy has not been investigated despite its added complexity. The purpose of this study is to investigate whether pre-dosing with metolazone confers a difference in efficacy and safety compared to administering it at the same time as furosemide.
