BackgroundHeart failure (HF) is a common condition associated with substantial cost, morbidity, and mortality. Because results of clinical trials in the acute decompensated heart failure (ADHF) setting have been mostly neutral, loop diuretics remain the mainstay of treatment.HypothesisLoop diuretic use may be associated with unfavorable outcomes.MethodsA MEDLINE literature search was performed to identify articles relating to heart failure and loop diuretics. The current evidence on the risks and benefits of loop diuretics for the treatment of ADHF is reviewed.ResultsLoop diuretics are associated with symptomatic improvements in congestion, urine output, and body weight, but have shown no long‐term mortality benefit. Loop diuretics, especially at high doses, are associated with worsened renal function and other poor outcomes.ConclusionsLoop diuretics still prove useful in HF treatment, but risk‐benefit analysis of these agents in the treatment of ADHF requires a well‐designed prospective study. Copyright © 2010 Wiley Periodicals, Inc.