Lasix (Furosemide) Dosing for a 1-Year-Old (6.68kg)
For a 1-year-old child weighing 6.68kg, administer furosemide at 0.5-2.0 mg/kg per dose, which translates to 3.34-13.36 mg per dose, given once or twice daily depending on clinical indication. 1
Weight-Based Dose Calculation
- Starting dose: 0.5 mg/kg = 3.34 mg per dose 1
- Typical therapeutic range: 0.5-2.0 mg/kg per dose 1
- Maximum dose: 2.0 mg/kg = 13.36 mg per dose 1
- Maximum daily dose: 6 mg/kg per day = 40.08 mg/day 1
Converting to mL Volume
The concentration of furosemide oral solution must be known to calculate mL dosing. Common concentrations include:
If using 10 mg/mL concentration (most common oral solution):
- Starting dose (3.34 mg) = 0.33 mL
- Maximum single dose (13.36 mg) = 1.34 mL
If using 40 mg/5 mL concentration (8 mg/mL):
- Starting dose (3.34 mg) = 0.42 mL
- Maximum single dose (13.36 mg) = 1.67 mL
Dosing Frequency and Titration
- Initial frequency: Once daily (QD) or twice daily (BID) 1
- Dose escalation: Increase gradually based on clinical response 1
- Dose adjustment intervals: Every 3-5 days, as clinical response is slow to appear 1
- For infants with normal renal function: A steep dose-response curve exists at 1 mg/kg IV, suggesting higher doses may not significantly increase diuretic response 2
Clinical Monitoring Requirements
- Weight: Daily monitoring to assess fluid loss 1
- Urine output: Target adequate diuresis 1
- Electrolytes: Monitor potassium, sodium, and other electrolytes shortly after initiating therapy and periodically thereafter 1
- Renal function: Monitor for nephrotoxicity, especially with prolonged use 2
- Minimum effective urinary excretion: 0.58 ± 0.33 μg/kg/min associated with significant diuresis 2
Critical Safety Considerations
- Hypokalemia risk: Most common adverse effect (3.6% in adults); consider potassium supplementation or potassium-sparing diuretics 3
- Volume depletion: Second most common adverse effect (4.6% in adults); monitor for signs of intravascular volume depletion 3
- Ototoxicity: Risk increases with higher doses and in renal impairment 1
- Long-term use complications: Secondary hyperparathyroidism and bone disease in infants; cholelithiasis in premature infants on total parenteral nutrition 2
Route-Specific Considerations
- Oral bioavailability: Highly variable and generally poor; absorption may be site-specific 4
- IV administration: More predictable response; if using IV route, same mg/kg dosing applies 2
- Response correlation: Diuretic effect correlates with urinary drug concentration, not plasma levels 4
Special Clinical Contexts
- Acute renal failure: Total daily dose should not exceed 100 mg in children with acute renal failure 2
- Combination therapy: If used with spironolactone for ascites, start furosemide at 0.5 mg/kg per dose twice daily 1
- Cystic fibrosis: These patients may have markedly enhanced diuretic response at lower doses 2