What is a good diuretic option for Congestive Heart Failure (CHF)?

Loop Diuretics Are the First-Line Diuretic Choice for CHF

Loop diuretics are the preferred diuretic agents for most patients with congestive heart failure (CHF), with furosemide being the most commonly used option. 1

Loop Diuretics: First-Line Options

Loop diuretics inhibit reabsorption of sodium and chloride at the loop of Henle and are essential for managing fluid retention in CHF:

• Furosemide: Most commonly prescribed, starting at 20-40 mg once or twice daily (maximum 600 mg daily), with duration of action 6-8 hours 1
• Torsemide: Better bioavailability and longer duration of action (12-16 hours), starting at 10-20 mg once daily (maximum 200 mg daily) 1, 2
• Bumetanide: Higher potency with better absorption, starting at 0.5-1.0 mg once or twice daily (maximum 10 mg daily), duration of action 4-6 hours 1, 3

Clinical Approach to Diuretic Therapy

Initiation and Titration

• Start with low doses of loop diuretics in outpatients with CHF 1
• Gradually increase dose until urine output increases and weight decreases (typically 0.5-1.0 kg daily) 1
• The ultimate goal is to eliminate clinical evidence of fluid retention using the lowest effective dose 1
• Combine with moderate dietary sodium restriction 1

Monitoring and Maintenance

• Once fluid retention resolves, maintain diuretic therapy to prevent recurrence of volume overload 1
• Consider having patients record daily weights and adjust diuretic dosage based on weight fluctuations beyond a specified range 1
• Monitor for electrolyte imbalances, especially when using high doses or combination diuretic therapy 1

Special Considerations

Diuretic Resistance

When patients become unresponsive to high doses of loop diuretics, consider:

• Escalation of loop diuretic dose 1
• Intravenous administration (bolus or continuous infusion) 1
• Addition of a thiazide diuretic (e.g., metolazone) - reserved for patients who don't respond to moderate or high-dose loop diuretics 1
• Causes of diuretic resistance include high sodium intake, use of NSAIDs, or significant impairment of renal function 1

Choice Between Loop Diuretics

• While furosemide is most commonly used, some patients may respond better to torsemide or bumetanide due to their superior oral bioavailability 1
• Torsemide has longer duration of action (12-16 hours) compared to furosemide (6-8 hours) 1
• Consider switching between loop diuretics if response is inadequate 4

Important Caveats

• Diuretics should not be used alone in treating CHF but should be combined with other guideline-directed medical therapies that reduce hospitalizations and prolong survival 1
• Inappropriate use of diuretics can lead to complications:
  • Too low doses: fluid retention, diminished response to ACE inhibitors, increased risk with beta-blockers 1
  • Too high doses: volume contraction, hypotension with ACE inhibitors, renal insufficiency 1
• With the exception of mineralocorticoid receptor antagonists (MRAs), the effects of diuretics on morbidity and mortality are uncertain 1

Thiazide Diuretics

• May be considered in patients with hypertension and CHF with mild fluid retention 1
• Can be added to loop diuretics for resistant edema (sequential nephron blockade) 1
• Examples include chlorthalidone, hydrochlorothiazide, and metolazone 1