What is the maximum dose of furosemide (Lasix)?

Maximum Dose of Furosemide

The maximum dose of furosemide varies by indication, but for most conditions, the maximum recommended dose is 600 mg/day for adults with severe edematous states, while in liver cirrhosis with ascites the maximum dose should not exceed 160 mg/day. 1, 2

Maximum Doses by Indication

Heart Failure

• Initial dose: 20-80 mg as a single dose 1
• Maintenance: Can be carefully titrated up to 600 mg/day in patients with clinically severe edematous states 1
• In acute heart failure: Initial IV dose of 20-40 mg, with total dose not exceeding 100 mg in first 6 hours and 240 mg during first 24 hours 3
• Doses above 160 mg/day indicate a need to escalate treatment in advanced heart failure 3

Liver Cirrhosis with Ascites

• Starting dose: 40 mg/day (typically combined with spironolactone 100 mg/day) 2
• Maximum dose: 160 mg/day 2, 3
• Exceeding this threshold is generally considered a marker of diuretic resistance in cirrhosis 2

Renal Failure

• High-dose furosemide (≥500 mg/day) may be used in refractory cases 4
• In acute renal failure in children, total daily dose should not exceed 100 mg 5
• In hemodialysis patients, doses up to 320 mg/day have been studied 6

Administration Considerations

Oral Administration

• When doses exceed 80 mg/day for prolonged periods, careful clinical observation and laboratory monitoring are particularly advisable 1
• For efficient and safe mobilization of edema, furosemide may be given on 2-4 consecutive days each week 1

Intravenous Administration

• IV administration is preferred in acute situations requiring rapid diuresis 3
• Continuous infusion may be considered after initial bolus in patients with volume overload 3, 7
• In diuretic-resistant heart failure, continuous infusion rates up to 160 mg/hour have been used successfully 7

Monitoring Requirements

• Regular monitoring of symptoms, urine output, renal function, and electrolytes is essential during furosemide therapy, especially at higher doses 2, 3
• When using high doses, monitor for:
  • Electrolyte disturbances, particularly hypokalemia and hyponatremia 2, 3
  • Renal function deterioration 2, 3
  • Ototoxicity (tinnitus, hearing loss) 4

Special Considerations

• Furosemide should be stopped if severe hyponatremia (serum sodium <120-125 mmol/L), progressive renal failure, worsening hepatic encephalopathy, or incapacitating muscle cramps develop 2
• In diuretic resistance, combining furosemide with thiazides or aldosterone antagonists may be more effective than further increasing the furosemide dose 3
• In pediatric patients, the maximum recommended dose is 6 mg/kg body weight 1

Caution

• While extremely high doses (up to 8 g/day) have been reported in case studies for refractory heart failure 4, these exceed standard recommendations and should only be considered in exceptional circumstances under close monitoring
• Oral administration is preferred in cirrhotic patients to avoid acute reductions in glomerular filtration rate associated with IV administration 3