What are the uses of furosemide, particularly in patients with congestive heart failure, cirrhosis of the liver, nephrotic syndrome, and hypertension?

Uses of Furosemide

Primary Indications

Furosemide is indicated for the treatment of edema associated with congestive heart failure, cirrhosis of the liver with ascites, renal disease including nephrotic syndrome, and as an adjunct in hypertension management. 1

Congestive Heart Failure

• Furosemide is indicated for treating fluid overload and congestion in heart failure patients, particularly when pulmonary edema or significant peripheral edema is present 2, 1
• In acute decompensated heart failure, IV furosemide 20-40 mg bolus should be administered for symptoms of congestion and volume overload 2
• For patients with evidence of significant volume overload, doses may be increased based on renal function and history of chronic diuretic use, with total furosemide dose remaining <100 mg in the first 6 hours and <240 mg during the first 24 hours 2
• Doses exceeding 160 mg/day indicate advanced disease requiring treatment escalation to combination therapy rather than further furosemide escalation alone 2

Cirrhosis of the Liver with Ascites

• In cirrhosis with ascites, furosemide 40 mg combined with spironolactone 100 mg should be started as a single morning dose 2
• The maximum dose is 160 mg/day in cirrhotic patients; exceeding this threshold indicates diuretic resistance requiring alternative strategies such as large volume paracentesis 2
• Oral administration is preferred over IV in cirrhotic patients due to good bioavailability and avoidance of acute reductions in GFR 2
• Therapy should be initiated in the hospital setting for patients with hepatic cirrhosis and ascites 1

Nephrotic Syndrome

• Furosemide is indicated for severe edema in nephrotic syndrome, with dosing of 0.5-2 mg/kg per dose IV or orally up to six times daily (maximum 10 mg/kg per day) 2
• IV furosemide 0.5-2 mg/kg should be administered at the end of albumin infusions in the absence of marked hypovolemia or hyponatremia 2
• High doses (>6 mg/kg/day) should not be given for periods longer than 1 week 2
• Infusions should be administered over 5-30 minutes to avoid hearing loss 2

Renal Disease

• Furosemide is particularly useful when an agent with greater diuretic potential is desired in patients with renal disease 1
• In chronic renal failure, furosemide has been used in high doses (up to 1000 mg/day orally) to produce moderate diuretic response 3
• Furosemide should NOT be used to prevent or treat acute kidney injury itself—only to manage volume overload that complicates AKI 2

Hypertension

• Oral furosemide may be used for treatment of hypertension alone or in combination with other antihypertensive agents 1
• Hypertensive patients who cannot be adequately controlled with thiazides will probably also not be adequately controlled with furosemide alone 1

Special Clinical Situations

Acute Respiratory Distress Syndrome (ARDS)

• In ARDS patients with fluid overload, furosemide should be administered when central venous pressure >8 mmHg with urine output <0.5 mL/kg/h or central venous pressure >4 mmHg with urine output ≥0.5 mL/kg/h 2

Diuretic Resistance

• When standard doses fail, combination therapy with thiazides (hydrochlorothiazide 25 mg) or aldosterone antagonists (spironolactone 25-50 mg) is preferred over escalating furosemide alone 2
• In nephrotic syndrome, amiloride should be used instead of spironolactone when potassium-sparing diuretics are needed 2

Critical Contraindications and Precautions

• Furosemide should be avoided in patients with marked hypovolemia, hypotension (SBP <90 mmHg), severe hyponatremia, acidosis, or anuria 2
• In hepatic coma and states of electrolyte depletion, therapy should not be instituted until the basic condition is improved 1
• Sudden alterations of fluid and electrolyte balance in patients with cirrhosis may precipitate hepatic coma; strict observation is necessary during diuresis 1
• If increasing azotemia and oliguria occur during treatment of severe progressive renal disease, furosemide should be discontinued 1

Monitoring Requirements

• Fluid status assessment (peripheral perfusion, blood pressure) should be monitored regularly 2
• Electrolytes (particularly potassium and sodium) require frequent monitoring 2
• Kidney function (urine output, estimated glomerular filtration rate) must be assessed 2
• Target weight loss should be 0.5 kg/day in patients without peripheral edema and 1.0 kg/day with peripheral edema 2

Common Pitfalls

• Ototoxicity is associated with rapid injection, severe renal impairment, use of higher than recommended doses, hypoproteinemia, or concomitant therapy with aminoglycosides or other ototoxic drugs 1
• For high-dose parenteral therapy, controlled intravenous infusion not exceeding 4 mg/minute should be used 1
• The most common adverse reactions are fluid and electrolyte disturbances, which are extensions of therapeutic effects 4