How the dose is calculated
Furosemide is dosed in mg/kg/day. Standard dosing is once daily for most oedema/heart failure indications; the higher-dose regimen divided twice daily is used for resistant oedema or significant renal impairment.
Typical dosing by indication
| Indication | Dose | Frequency | Max |
|---|---|---|---|
| Standard | 2 mg/kg/day | once daily | 40 mg/day |
| Higher-dose | 4 mg/kg/day | every 12h (2×/day) | 160 mg/day |
Clinical use
- Furosemide is a loop diuretic used for fluid overload in heart failure, nephrotic syndrome, and other oedematous states, and to promote diuresis in some renal and hepatic conditions.
- IV furosemide acts within minutes, faster than the oral route (30–60 minutes to onset) — the IV route is preferred when rapid diuresis is needed.
- Electrolyte disturbances (hypokalaemia, hyponatraemia, hypochloraemic alkalosis) are common with ongoing use — monitor electrolytes, particularly with higher doses or prolonged therapy.
- Ototoxicity risk rises with rapid IV administration of high doses, especially alongside other ototoxic drugs (e.g. aminoglycosides) — give slow IV push or infusion for larger doses.
Frequently asked questions
What is furosemide used for?
Furosemide is a loop diuretic used to treat fluid overload from conditions like heart failure, nephrotic syndrome, and certain kidney and liver diseases, by increasing urine output.
Why is IV furosemide used instead of oral?
IV furosemide starts working within minutes, much faster than the 30–60 minutes oral furosemide takes to act, making it preferred when rapid diuresis is clinically needed.
What electrolyte problems can furosemide cause?
It commonly causes low potassium, low sodium, and a metabolic alkalosis from chloride loss — electrolytes should be monitored periodically, especially with higher doses or longer courses.
Can furosemide affect hearing?
Yes — rapid IV administration of high doses carries a risk of ototoxicity (hearing/balance disturbance), particularly when combined with other ototoxic drugs like aminoglycosides. Larger IV doses should be given slowly.
References
- British National Formulary for Children (BNFc) — Furosemide.
- International Pediatric Nephrology Association. Guidelines for the Management of Idiopathic Nephrotic Syndrome.
- Heart Failure Society of America. Comprehensive Heart Failure Practice Guideline.