Furosemide
LASIX
What it isLoop diuretic blocking the NKCC2 cotransporter; volume overload in heart failure, kidney disease and cirrhosis.
Why this oneRapid IV action makes it the workhorse for acute pulmonary edema, but oral absorption is less predictable than torsemide.
What limits itVolume depletion, hypokalemia, hyponatremia and hypomagnesemia require weight, renal-function and electrolyte follow-up.
FDA-approved for
- edema (1966)
- hypertension (~1966)
FDA label
Read the full label on DailyMed ↗
| FDA dosing | Population | Start | Target | Max |
|---|---|---|---|---|
| Edema | Adults | 20–80 mg QD | individualized, QD–BID | 600 mg/day (severe edema) |
| Edema | Pediatric | 2 mg/kg QD | 6 mg/kg | |
| Hypertension | Adults | 40 mg BID (80 mg/day) | adjust to response |
Titration May increase by 20–40 mg no sooner than 6–8 h after the previous dose until desired effect (edema)
Renal Undefined
Hepatic Initiate in hospital in cirrhosis with ascites; sudden fluid/electrolyte shifts may precipitate hepatic coma
Edema may be mobilized by dosing 2–4 consecutive days/week
Instructions
- Discontinue if increasing azotemia/oliguria occurs in severe progressive renal disease
Contraindications
- Anuria
Cautions
- Ototoxicity (tinnitus, reversible/irreversible hearing loss) — risk with rapid injection, renal impairment, high doses, aminoglycosides/other ototoxics
- Fluid/electrolyte depletion
- Hepatic coma risk in cirrhosis
Adverse reactions
- Hepatic encephalopathy (in hepatocellular insufficiency)
- Pancreatitis
- Jaundice
- Anaphylactoid reactions
- Interstitial nephritis
- Tinnitus/hearing loss
- Blood dyscrasias (aplastic anemia, thrombocytopenia, agranulocytosis)
- Severe skin reactions (TEN, SJS)
- Orthostatic hypotension
- Hyperglycemia, hyperuricemia
Pregnancy Undefined
Lactation Undefined
NO BOXED WARNINGS
Principal riskVolume depletion with hypokalemia and hyponatremia
Cost, est. cash$4–$80/month
Generic entry1985
Classes and tags
Clinical profile
Legacy pregnancy categoryC
Defining liabilityVolume depletion, electrolyte loss, kidney injury and ototoxicity at high exposure.
Mechanism of action: Furosemide ballicule
Open Furosemide in the interactive console ↗
Memory aids: mascots and interaction avatars
Roller coaster → loop diuretic
Bananas dispersing → ↓ serum potassium
