Please check your internet connection and try again.
# Furosemide
## Overview
Furosemide is a loop diuretic used to treat fluid overload (edema) associated with congestive heart failure, liver cirrhosis, and renal disease, including nephrotic syndrome. It is also used to treat high blood pressure, alone or in combination with other antihypertensives.
## Primary Indications
* Edema due to congestive heart failure, liver disease, and renal disease.
* Hypertension.
## Adult Dosing
* **Edema:**
* **Initial:** 20-80 mg orally once daily. May be given in divided doses.
* **Maintenance:** Adjust dose based on response. Doses may range from 20-40 mg orally once daily to 80-120 mg orally twice daily.
* **Maximum:** Up to 600 mg orally per day has been used in severe cases, but this is uncommon and requires careful monitoring.
* **Hypertension:**
* **Initial:** 40 mg orally twice daily.
* **Maintenance:** Adjust dose based on response. May be increased to 80-120 mg orally per day in two divided doses.
* **Maximum:** Generally not recommended for monotherapy; typically used in combination. Maximum effective dose is usually 80 mg/day.
## Pediatric Dosing
* **Edema:**
* **Initial:** 1-2 mg/kg orally once daily, not to exceed 40 mg/day.
* **Maintenance:** Adjust dose based on response. Typically 1-4 mg/kg/day orally in one or two divided doses.
* **Maximum:** 6 mg/kg orally per day.
## Dose Adjustments
* **Renal Impairment:** Dose may need to be increased in patients with renal impairment due to decreased protein binding and increased clearance. However, caution is advised as it can also worsen renal function. In severe renal impairment, intermittent or continuous intravenous infusions may be more effective.
* **Hepatic Impairment:** Monitor closely for electrolyte and fluid imbalances.
## Contraindications
* Anuria.
* History of hypersensitivity to furosemide or sulfonamides.
## Adverse Effects
Common: Dizziness, lightheadedness, electrolyte imbalance (hypokalemia, hyponatremia, hypochloremia), dehydration, hypotension, hyperglycemia, hyperuricemia.
Less Common: Ototoxicity (especially with rapid IV administration or in patients with renal impairment), skin rash, pancreatitis, blood dyscrasias.
## Key Drug Interactions
* **Aminoglycosides and other ototoxic drugs:** Increased risk of ototoxicity.
* **NSAIDs:** May reduce furosemide's diuretic and antihypertensive effects; increased risk of renal impairment.
* **ACE inhibitors/ARBs:** Increased risk of hypotension and renal dysfunction.
* **Potassium-sparing diuretics, ACE inhibitors, ARBs, K+ supplements:** Increased risk of hyperkalemia.
* **Digoxin:** Increased risk of digoxin toxicity due to furosemide-induced hypokalemia.
* **Lithium:** Reduced renal clearance of lithium, increasing risk of lithium toxicity.
## Monitoring
* Electrolytes (sodium, potassium, chloride)
* Renal function (BUN, creatinine)
* Fluid balance (intake/output, weight)
* Blood pressure
* Blood glucose (in diabetic patients)
* Uric acid (in patients with gout)
* Hearing (if ototoxicity is suspected)
## Clinical Pearls
* Furosemide is a potent diuretic; monitor patients closely for signs of dehydration and electrolyte depletion.
* Oral administration is generally preferred. Intravenous administration may be used for more rapid onset or in patients unable to take oral medications.
* Rapid IV administration can increase the risk of ototoxicity. Administer IV furosemide slowly, typically over 30-60 minutes.
* For edema, dosing is often weight-based and adjusted based on urine output and daily weight loss.
* Concomitant potassium supplementation or use of potassium-sparing diuretics may be necessary to prevent or manage hypokalemia, especially with higher doses or prolonged therapy.
***
*This information is intended for healthcare professionals. Always consult the current prescribing information and institutional protocols for complete and up-to-date guidance.*
