What is the maximum per day infusion dose of Lasix (furosemide)?

Maximum Per Day Infusion Dose of Furosemide

The maximum daily dose of intravenous furosemide is 240 mg in the first 24 hours for acute heart failure, with a maximum infusion rate of 4 mg/min, though higher doses up to 600 mg/day may be used in severe edematous states with careful monitoring. 1, 2

Standard Maximum Dosing by Clinical Context

Acute Heart Failure

• Total furosemide dose should remain <100 mg in the first 6 hours and <240 mg during the first 24 hours 1
• Initial IV bolus: 20-40 mg over 1-2 minutes, with higher doses (up to 80 mg) for patients already on chronic oral diuretics 1
• Continuous infusion: 5-10 mg/hour, with maximum infusion rates not exceeding 4 mg/min 1
• Doses of 250 mg and above must be given by infusion over 4 hours to prevent ototoxicity 1

Cirrhosis with Ascites

• Maximum oral dose: 160 mg/day, typically combined with spironolactone 3, 1
• Initial dose: 40 mg/day, increased every 2-3 days up to 160 mg/day 3
• Exceeding 160 mg/day indicates diuretic resistance requiring alternative strategies (large volume paracentesis) rather than further dose escalation 1
• High doses are associated with severe electrolyte disturbance and metabolic alkalosis 3

Severe Edematous States

• The FDA label indicates doses may be carefully titrated up to 600 mg/day in severe edematous states 2
• In refractory cardiac failure, doses up to 700 mg/day (mean maintenance) have been used successfully, with peak doses reaching 8 g/day in one case report 4
• However, in chronic renal insufficiency, maximal response is attained with single IV doses of 120-160 mg, with no benefit from larger single doses 5

Critical Infusion Rate Considerations

• Infusions must be administered over 5-30 minutes to avoid hearing loss 1
• Maximum infusion rate: 4 mg/min 1
• Rapid IV administration increases risk of ototoxicity, particularly at high doses 1, 2

Mandatory Monitoring Requirements

During High-Dose Infusion

• Urine output: hourly monitoring 1
• Blood pressure: every 15-30 minutes in first 2 hours 1
• Electrolytes (sodium, potassium): within 6-24 hours 1
• Renal function: within 24 hours 1
• Bladder catheter placement recommended for rapid assessment of treatment response 1

Ongoing Monitoring

• Daily weights targeting 0.5-1.0 kg loss per day 1
• Electrolytes every 3-7 days during initial titration 1
• Serum creatinine and sodium concentration, particularly during first weeks 1

Absolute Contraindications to Dose Escalation

Stop furosemide immediately if any of the following develop: 1

• Severe hyponatremia (serum sodium <120-125 mmol/L)
• Severe hypokalemia (<3 mmol/L)
• Progressive renal failure or acute kidney injury
• Anuria
• Marked hypotension (SBP <90 mmHg without circulatory support)
• Worsening hepatic encephalopathy (in cirrhotic patients)
• Incapacitating muscle cramps

Management of Inadequate Response

Rather than escalating furosemide beyond 160-240 mg/day, consider combination therapy: 1

• Add thiazide diuretic (hydrochlorothiazide 25 mg orally)
• Add aldosterone antagonist (spironolactone 25-50 mg orally)
• Sequential nephron blockade is more effective than monotherapy escalation 1

Alternative Strategies

• In acute pulmonary edema: IV nitroglycerin is superior to high-dose furosemide alone 1
• In cirrhosis exceeding 160 mg/day: large volume paracentesis with albumin replacement 1
• In refractory cases: consider venovenous isolated ultrafiltration 1

Common Pitfalls to Avoid

• Do not administer furosemide to hypotensive patients expecting hemodynamic improvement—it worsens tissue perfusion and precipitates cardiogenic shock 1
• Do not exceed 6 mg/kg/day for periods longer than 1 week in pediatric patients 1
• Do not use furosemide to prevent or treat acute kidney injury—only for managing volume overload that complicates AKI 1
• Avoid evening doses causing nocturia and poor adherence 1
• Do not escalate beyond 80-160 mg daily without adding a second diuretic due to ceiling effect 1

Special Population Considerations

Pediatric Patients

• Maximum dose: 6 mg/kg/day 1
• Doses greater than 6 mg/kg/day not recommended for >1 week 1
• Monitor for nephrocalcinosis/nephrolithiasis, especially in premature infants 2

Elderly Patients

• Start at low end of dosing range due to decreased renal function 2
• More likely to experience toxic reactions due to impaired renal function 2

Renal Insufficiency

• In chronic renal insufficiency (creatinine clearance <20 ml/min), maximal response attained with 120-160 mg single IV doses 5
• No benefit from larger single doses in this population 5