Severe congestive heart failure
Spironolactone is indicated in Congestive heart failure, Hepatic cirrhosis with ascites and oedema, Nephrotic syndrome, Primary hyperaldosteronism, Essential hypertension, For the treatment of patients with hypokalemia
Spironolactone is a specific pharmacologic antagonist of aldosterone, acting primarily through competitive binding of receptors at the aldosterone-dependent sodium-potassium exchange site in the distal convoluted renal tubule. Spironolactone causes increased amounts of sodium and water to be excreted, while potassium is retained. Spironolactone acts both as a diuretic and as an antihypertensive drug by this mechanism. It may be given alone or with other diuretic agents which act more proximally in the renal tubule. Aldosterone interacts with a cytoplasmic mineralocorticoid receptor to enhance the expression of the Na+ K+ ATPase and the Na+ channel involved in a Na+ K+ transport in the distal tubule . Spironolactone bind to this mineralcorticoid receptor, blocking the actions of aldosterone on gene expression. Aldosterone is a hormone; its primary function is to retain sodium and excrete potassium in the kidneys.
ACE inhibitors: Concomitant administration of ACE inhibitors with potassium-sparing diuretics has been associated with severe hyperkalemia.
Alcohol, barbiturates, or narcotics: Potentiation of orthostatic hypotension may occur.
Corticosteroids, ACTH: Intensified electrolyte depletion, particularly hypokalemia, may occur.
Lithium: Lithium generally should not be given with diuretics. Diuretic agents reduce the renal clearance of lithium and add a high risk of lithium toxicity.
Digoxin: Spironolactone has been shown to increase the half-life of digoxin.
Gynaecomastia may develop in association with the use of Spironolactone. Other adverse reactions are: GI symptoms including cramping and diarrhoea, drowsiness, lethargy, headache, urticaria, mental confusion, impotence, irregular menses or amenorrhoea and post-menopausal bleeding.
Pregnancy: Spironolactone should not be used during pregnancy
Lactation: Canrenone, an active metabolite of Spironolactone, appears in breast milk. If use of the drug is deemed essential an alternative method of infant feeding should be instituted.
All patients receiving diuretic therapy should be observed for evidence of fluid or electrolyte imbalance. Hyperkalemia may occur in patients with impaired renal function or excessive potassium intake and can cause cardiac irregularities, which may be fatal.
Potassium-sparing diuretics, Potassium-sparing diuretics & Aldosterone antagonists
Symptoms of overdosage include drowsiness, mental confusion, dizziness, diarrhea and vomiting etc. Patients should induce vomiting or evacuate the stomach by lavage during Spironolactone overdoasge.
Store in a cool and dry place protected from light. Keep out of reach of children.
