Lasix Retard (Furosemide)

• Lasix Retard, a loop diuretic, is used to treat conditions characterized by fluid retention.
• Edema associated with congestive heart failure: reduces excess fluid by increasing urinary output, relieving swelling and dyspnea.
• Edema due to liver cirrhosis: promotes diuresis to lower abdominal and peripheral fluid accumulation.
• Edema due to renal disease: assists in removing retained water and salts when kidney function is impaired.
• Hypertension: lowers blood volume, contributing to a decrease in systemic arterial pressure.

• Furosemide acts by inhibiting the Na⁺/K⁺/2Cl⁻ cotransporter in the thick ascending limb of the loop of Henle. This blockade reduces reabsorption of sodium, chloride and potassium, leading to increased excretion of these ions together with water, thereby decreasing extracellular fluid volume and blood pressure.

Common Side Effects

• Increased urinary frequency: more frequent urination due to diuretic action.
• Dizziness or light‑headedness: result of reduced blood volume.
• Electrolyte imbalance (especially low potassium): loss of potassium with urine.
• Dehydration: excessive fluid loss can cause thirst and dry mouth.
• Headache: may accompany changes in blood pressure.

Serious or Rare Side Effects

• Severe dehydration: can lead to hypotension and renal impairment.
• Ototoxicity: rare hearing loss, especially with high doses.
• Significant electrolyte disturbances (e.g., hyponatremia, hypokalemia): may cause cardiac arrhythmias.
• Allergic reactions: rash, itching, or swelling.
• Acute renal failure: abrupt loss of kidney function in susceptible individuals.

• Before initiating therapy, evaluate renal function, electrolyte status and blood pressure.
• Renal function: assess baseline creatinine and monitor periodically.
• Electrolytes: check serum potassium and sodium levels regularly.
• Blood pressure: monitor for hypotension, especially after the first dose.
• Concurrent diuretics: avoid additive fluid loss by reviewing other diuretic use.
• Pregnancy and lactation: use only if benefits outweigh potential risks.
• Store at ambient temperature: keep below 25°C, retain in original packaging and protect from moisture.

Furosemide may interact with several drug classes, requiring careful management.

Major Interactions (Avoid)

• Aminoglycoside antibiotics: increased risk of ototoxicity.
• NSAIDs: may diminish diuretic efficacy and affect renal function.
• Lithium: can raise lithium concentrations, leading to toxicity.

Moderate Interactions (Monitor Closely)

• ACE inhibitors or ARBs: additive blood‑pressure‑lowering effect.
• Antidiabetic agents: diuresis may alter glucose control, necessitating dose adjustment.