Frusemide & Spironolactone combination is indicated in-
Chronic congestive heart failure
Hepatic cirrhosis, with collection of fluid in the abdominal cavity (ascites)
Swelling due to excess fluid retention (edema)
Resistant edema associated with secondary hyperaldosteronism
Potassium-sparing diuretics, Potassium-sparing diuretics & Aldosterone antagonists
Spironolactone (potassium sparing diuretic) and Furosemide (loop diuretic) have different but complementary mechanisms and sites of action. Therefore, when given together they produce additive or synergistic diuretic. The Furosemide component inhibits the Na+/K+/2Cl- co-transporter in the ascending Loop of Henle and blocks the reabsorption of sodium, potassium and chloride ions; thereby increasing the quantity of sodium and the volume of water excreted in the urine. This characteristically induces potassium loss. The spironolactone component inhibits the reabsorption of sodium in exchange for potassium at the distal tubule by antagonising the action of aldosterone so that sodium excretion is greatly favoured and the excess loss of potassium, induced by the Furosemide, is reduced
Dosage & Administration
Furosemide 20 and spironolactone 50 mg: 1 to 4 tablets daily according to the patient’s response.
Furosemide 40 and spironolactone 50 mg: For previously stabilized patients 1 to 2 tablets daily, orally.
When taken together with ACE inhibitors or potassium salts there is an increased risk of hyperkalemia. Spironolactone increases the levels of cardiac glycosides such as digoxin in the blood and this may result in digitalis toxicity. Corticosteroids may cause hypokalemia if they are used with Spironolactone. The blood pressure lowering and diuretic effects of Furosemide may be reduced or abolished when used together with indomethacin and possibly other non-steroidal anti-inflammatory drugs (NSAIDs). Furosemide may increase the ototoxicity of aminoglycoside antibiotics. Simultaneous administration of sucralfate and Furosemide may reduce the natriuretic and anti-hypertensive effect of Furosemide.
Contraindicated in patients with anuria, acute renal insufficiency, rapidly deteriorating or severe impairment of renal function (creatinine clearance <30 ml/min), hyperkalaemia, Addison’s disease and in patients who are hypersensitive to Spironolactone, Furosemide or sulphonamides.
Spironolactone may give rise to headache and drowsiness and gastrointestinal distress, including cramp and diarrhoea. Ataxia, mental confusion, and skin rashes have been reported as side effect. Gynaecomastia is not uncommon and in rare cases breast enlargement may persist. Other endocrine disorders including hirsutism, deepening of the voice, menstrual irregularities and impotence. Transient increase in blood-urea-nitrogen concentrations may occur and mild acidosis has been reported. Spironolactone may cause hyponatremia and hyperkalemia. Excessive diuresis may result in dehydration and reduction in blood volume with circulatory collapse with the possibility of vascular thrombosis and embolism particularly in elderly patients. Serious depletion of potassium and magnesium may lead to cardiac arrhythmias.