Tab Lasix (furosemide)

# Tab Lasix (furosemide) ## Overview Furosemide is a potent loop diuretic that inhibits the reabsorption of sodium and chloride in the thick ascending limb of the loop of Henle, leading to a significant increase in the excretion of water, sodium, potassium, chloride, calcium, and magnesium. ## Primary Indications * Edema associated with congestive heart failure (CHF) * Edema associated with liver cirrhosis * Edema associated with renal disease, including nephrotic syndrome * Management of hypertension (often in combination with other antihypertensives) ## Adult Dosing * **Edema:** * Initial dose: 20-80 mg orally once daily. * Subsequent doses may be adjusted based on response, typically every 6-8 hours. * The dose may be increased by 20-40 mg and administered at intervals of 6-8 hours. * Maximum daily dose: 600 mg (higher doses may be used in severe refractory edema under close medical supervision). * **Hypertension:** * Initial dose: 40 mg orally once daily. * Dose may be adjusted based on response. * Maximum daily dose: 80 mg (though higher doses are not generally recommended for uncomplicated hypertension). ## Pediatric Dosing * **Edema:** * Neonates: 0.5-2 mg/kg/dose orally every 12-24 hours. * Infants and Children: 1-2 mg/kg/dose orally once daily. * Subsequent doses can be increased by 1-2 mg/kg/dose every 6-8 hours. * Maximum daily dose: 6 mg/kg. * **Note:** Pediatric dosing is highly individualized and often requires titration. Always refer to specific pediatric guidelines or institutional protocols. ## Dose Adjustments * **Renal Impairment:** Dose may need to be increased in renal impairment to achieve the same diuretic effect due to reduced drug delivery to the site of action. However, caution is advised with very high doses. * **Hepatic Impairment:** Caution is advised; dose may need to be reduced in severe hepatic impairment due to altered drug metabolism and increased sensitivity to electrolyte imbalances. ## Contraindications * Anuria * Hypersensitivity to furosemide or sulfonamides ## Adverse Effects * **Common:** Dizziness, lightheadedness, electrolyte imbalances (hypokalemia, hyponatremia, hypochloremia, hypomagnesemia, hypocalcemia), dehydration, hypotension, hyperglycemia, hyperuricemia. * **Serious:** Severe electrolyte depletion, ototoxicity (especially with rapid IV administration or high doses), Stevens-Johnson syndrome, agranulocytosis, aplastic anemia, thrombocytopenia. ## Key Drug Interactions * **Aminoglycosides and other ototoxic drugs:** Increased risk of ototoxicity. * **Corticosteroids:** Increased risk of hypokalemia. * **Digoxin:** Increased risk of digoxin toxicity due to furosemide-induced hypokalemia. * **NSAIDs:** May reduce diuretic and antihypertensive effects, and increase risk of renal impairment. * **Potassium-sparing diuretics (e.g., spironolactone):** May require closer monitoring of potassium levels. * **Lithium:** Increased risk of lithium toxicity. * **Antihypertensives:** Additive hypotensive effect. ## Monitoring * **Electrolytes:** Serum electrolytes (sodium, potassium, chloride, magnesium, calcium) especially with chronic use or in patients at risk for depletion. * **Renal function:** Serum creatinine, BUN. * **Fluid balance:** Daily weights, intake and output. * **Blood pressure:** Especially in patients treated for hypertension. * **Hearing:** Assess for tinnitus or hearing loss. * **Blood glucose:** In diabetic patients. * **Uric acid:** In patients with a history of gout. ## Clinical Pearls * Administer oral doses with food or milk to minimize gastrointestinal upset. * Rapid intravenous administration can cause ototoxicity; infuse slowly (e.g., over 20-30 minutes for doses up to 20 mg, longer for higher doses). * Monitor for signs of dehydration and electrolyte depletion (e.g., dry mouth, thirst, muscle cramps, fatigue, dizziness). * Patients on furosemide may require potassium supplementation or concurrent use of a potassium-sparing diuretic, depending on their serum potassium levels and clinical status. * The diuretic effect is typically seen within 1 hour of oral administration and lasts for 6-8 hours. --- **Disclaimer:** This information is intended for clinical use and is not exhaustive. Always consult the current official prescribing information and relevant clinical guidelines for complete details, including specific dosage adjustments based on patient factors and local protocols.