What is the maximum dose of Lasix (furosemide) for intravenous administration?

Maximum Intravenous Push Dose for Furosemide

The maximum rate for intravenous push administration of furosemide is 4 mg/min, and individual bolus doses should not exceed 80-100 mg given over 1-2 minutes for standard IV push administration. 1

FDA-Approved Administration Guidelines

The FDA label provides explicit instructions for IV push furosemide administration 1:

• Standard IV bolus: 20-40 mg given slowly over 1-2 minutes as initial dose
• Repeat dosing: May increase by 20 mg increments, given not sooner than 2 hours after previous dose
• Acute pulmonary edema: Initial 40 mg IV push over 1-2 minutes; if inadequate response after 1 hour, may increase to 80 mg IV push over 1-2 minutes
• Maximum infusion rate: When using high-dose parenteral therapy via continuous infusion, rate must not exceed 4 mg/min 1

High-Dose Administration Protocols

For doses exceeding standard bolus amounts, specific precautions apply 1:

• High-dose therapy: Must be given as controlled IV infusion, not rapid push
• Preparation requirements: Add furosemide to normal saline, lactated Ringer's, or D5W after adjusting pH above 5.5
• Rate limitation: Controlled infusion at ≤4 mg/min to prevent ototoxicity 1
• Avoid acidic solutions: Do not mix with acidic medications (labetalol, ciprofloxacin, amrinone, milrinone) as precipitation occurs 1

Maximum Dosing by Clinical Context

Acute Heart Failure

• First 6 hours: Total dose should not exceed 100 mg 2
• First 24 hours: Total dose should not exceed 240 mg 2
• Continuous infusion: 5-10 mg/hour, with maximum rate of 4 mg/min during administration 2

Cirrhosis with Ascites

• Maximum daily dose: 160 mg/day (typically combined with spironolactone) 3, 2
• Exceeding this threshold: Indicates diuretic resistance requiring alternative strategies 3, 2

Pediatric Patients

• Standard dose: 1 mg/kg IV push given slowly 1
• Maximum single dose: 6 mg/kg body weight 1
• Premature infants: Should not exceed 1 mg/kg/day 1

Critical Safety Considerations

Ototoxicity Prevention

The rate of administration is crucial to prevent hearing loss 2, 4:

• Infusions must be given over 5-30 minutes when doses exceed standard bolus amounts
• Rapid IV push of large doses significantly increases ototoxicity risk
• Maximum rate of 4 mg/min must be strictly observed 1

Absolute Contraindications to Administration

Do not administer furosemide IV push if 2, 4:

• Anuria is present
• Systolic blood pressure <90 mmHg without circulatory support
• Severe hyponatremia (serum sodium <120-125 mmol/L)
• Marked hypovolemia or hypotension
• Within 12 hours of last fluid bolus or vasopressor administration

Common Pitfalls to Avoid

Never push large doses rapidly 1: The 1-2 minute administration time applies only to standard 20-80 mg boluses. Higher doses require controlled infusion at ≤4 mg/min to prevent ototoxicity and acute hemodynamic changes.

Do not exceed 100 mg in first 6 hours in acute heart failure 2: Aggressive early dosing beyond this threshold increases nephrotoxicity risk without improving outcomes.

Avoid mixing with acidic solutions 1: Furosemide has pH ~9 and precipitates below pH 7. Never add to running IV lines containing acidic medications.

Monitor for acute renal deterioration 4: Creatinine increases >0.3 mg/dL during treatment are associated with 3-fold higher mortality risk. Doses >60-80 mg daily significantly increase renal function deterioration.