Recommended Initial Treatment for Ascites with Spironolactone and Bumetanide

For first-episode ascites, start with spironolactone 100 mg/day alone, not in combination with bumetanide initially. 1, 2

Initial Treatment Strategy

The evidence strongly supports spironolactone monotherapy for new-onset ascites:

Start spironolactone at 100 mg/day as monotherapy for first-episode ascites, as this generates adequate response with fewer side effects compared to combination therapy 1, 2
Reserve loop diuretics (furosemide or bumetanide) for patients with long-standing or recurrent ascites, where combination therapy is more effective 1
The FDA label for spironolactone recommends initiating at 100 mg daily for cirrhotic ascites, administered in single or divided doses 3

Add a loop diuretic only after spironolactone monotherapy fails:

If spironolactone 100 mg/day is ineffective after 3-5 days (accounting for the drug's long half-life), increase to 200 mg, then 300 mg, and finally 400 mg/day before adding a loop diuretic 1, 2
Only add furosemide (starting at 40 mg/day) or bumetanide when spironolactone reaches 400 mg/day without adequate response 1
Bumetanide may improve natriuresis in patients with suboptimal response to furosemide, but it is not first-line 1

If you must use bumetanide:

Bumetanide is similar to furosemide in action and efficacy 1
The typical furosemide dose is 40-160 mg/day; bumetanide is approximately 40 times more potent than furosemide, so 2 mg bumetanide ≈ 80 mg furosemide 1
Your proposed dose of bumetanide 2 mg is reasonable but should only be added after maximizing spironolactone to 400 mg/day 1

Monitor closely to prevent complications:

Check electrolytes, creatinine, and weight within 3-5 days of initiation and weekly during titration 1, 2
Stop or reduce diuretics if: serum sodium <120-125 mmol/L, creatinine increases >0.3 mg/dL, potassium >6 mmol/L or <3 mmol/L 1, 2
Target weight loss of 0.5 kg/day without peripheral edema, or up to 1 kg/day with edema 1, 2
Increase doses cautiously with at least 72-hour intervals between adjustments due to spironolactone's long half-life 1, 2

Sodium restriction is essential and often overlooked:

Prescribe moderate sodium restriction (2 g or 90 mmol/day) 1
Monitor compliance with spot urine sodium/potassium ratio; if >1, patient should be losing weight 1
Formal dietician consultation should be considered 1

Starting with combination therapy for first-episode ascites is inappropriate:

The 2021 AASLD guidelines explicitly state that spironolactone alone is adequate for first-episode ascites 1, 2
Combination therapy increases risk of electrolyte disturbances (20-40% incidence) including hyponatremia, hyperkalemia, and renal impairment 1
Do not increase doses more frequently than every 72 hours due to spironolactone's pharmacokinetics 1, 2
Do not restrict fluids unless serum sodium <125 mmol/L 1, 2

For tense (grade 3) ascites:

Perform large-volume paracentesis first with albumin (6-8 g per liter drained), then initiate maintenance diuretic therapy 1, 2

For chronic kidney disease:

Use higher doses of loop diuretics and lower doses of aldosterone antagonists 1, 2

For painful gynecomastia from spironolactone: