Description
Spironolactone Pharmacodynamics
Spironolactone is a potassium-saving diuretic, a specific prolonged-acting aldosterone antagonist (mineralocorticosteroid hormone of the adrenal cortex). In the distal parts of the nephron, spironolactone prevents sodium and water retention by aldosterone and inhibits potassium withdrawal effect of aldosterone, reduces the synthesis of permease in aldosterone-dependent section of the collecting tubes and distal tubules. By binding to aldosterone receptors, it increases excretion of sodium ions, chlorine ions and water with urine, decreases excretion of potassium ions and urea, reduces urine acidity.
Increased diuresis is due to the diuretic effect, which is not permanent. Diuretic effect appears on the 2nd-5th day of treatment.
Indications
Essential hypertension (as part of combination therapy).
Edematous syndrome in chronic heart failure (can be used in monotherapy and in combination with standard therapy).
Conditions in which secondary hyperaldosteronism may be found, including liver cirrhosis accompanied by ascites and/or edema, nephrotic syndrome, and other conditions accompanied by edema.
Hypokalemia/hypomagnesemia (as an adjunct to its prophylaxis during treatment with diuretics and when other methods of potassium correction are impossible).
Primary hyperaldosteronism (Conn’s syndrome) – for short preoperative treatment.
Contraindications
Hypersensitivity to the components of the drug, Addison’s disease, hyperkalemia, hyponatremia, severe renal failure (creatinine clearance less than 10 ml/min), anuria, simultaneous use of eplerenone and other potassium-saving diuretics, potassium preparations, pregnancy and breastfeeding, children under 3 years of age (due to the solid dosage form), lactose intolerance, lactase deficiency, glucose-galactose malabsorption syndrome (the drug contains lactose).
Dosage and administration
- Orally. If it is necessary to use spironolactone 25 mg, other manufacturers drugs in dosage form “tablets” or “capsules” in dosage form of 25 mg should be prescribed to ensure the dosage regimen stated below.
- Essential Hypertension.
- The daily dose for adults is usually 50-100 mg once and may be increased to 200 mg, and the dose should be increased gradually, once every 2 weeks. To achieve an adequate response to therapy, the drug should be taken for at least 2 weeks. If necessary, dose adjustment is performed.
- Idiopathic hyperaldosteronism.
- The drug is prescribed in a dose of 100-400 mg/day.
- Severe hyperaldosteronism and hypokalemia
- The drug is prescribed at a dose of 300 mg/day (maximum 400 mg/day) at 2-3 doses; if condition improves, the dose is gradually reduced to 25 mg/day.
- Hypokalemia and/or hypomagnesemia
- In hypokalemia and/or hypomagnesemia caused by diuretic therapy the drug is prescribed at a dose of 25-100 mg/day, once or in several doses. The maximum daily dose is 400 mg if oral potassium preparations or other methods of potassium deficiency supplementation are ineffective.
- Diagnosis and treatment of primary hyperaldosteronism
- As a diagnostic agent in a short diagnostic test: 400 mg/day for 4 days, distributed in several intakes per day. If blood potassium content increases during drug administration and decreases after drug withdrawal, primary hyperaldosteronism may be suspected.
- In long-term diagnostic test: in the same dose for 3-4 weeks. If correction of hypokalemia and arterial hypertension is achieved, the presence of primary hyperaldosteronism can be assumed.
- A short course of preoperative therapy for primary hyperaldosteronism
- Once the diagnosis of hyperaldosteronism has been established by more accurate diagnostic methods, SPIRONOLACTON should be taken at 100-400 mg/day, divided into 1-4 doses per day for the duration of preparation for surgical intervention. If surgical intervention is not indicated, SPIRONOLACTON is used for long-term supportive therapy, using the lowest effective dose that is chosen individually for each patient.
- Edema against a background of nephrotic syndrome
- Daily dose for adults is usually 100-200 mg/day. Spironolactone has not been found to affect the underlying pathological process, and therefore the use of this drug is recommended only when other therapies are ineffective.
- Edema syndrome in chronic heart failure
- Daily, for 5 days, 100-200 mg/day in 2-3 doses, in combination with “loop” or thiazide diuretic. Depending on the effect, the daily dose is reduced to 25 mg. The maintenance dose is selected individually. Maximum dose is 200 mg/day.
- Edema in cirrhosis
- If urinary sodium to potassium ion ratio (Na+/K+) exceeds 1.0, the daily dose for adults is usually 100 mg. If the ratio is less than 1.0, the daily dose for adults is usually 200-400 mg. The maintenance dose is adjusted individually.
- Edema in children.
- The initial dose in children over 3 years of age is 1.0-3.3 mg/kg body weight, or 30-90 mg/m2/day in 1-4 doses. The dose is adjusted in 5 days and if necessary, it is increased in 3 times more than the original dose.
- Administration in elderly patients
- It is recommended to start treatment with the minimum dose and titrate it to reach the maximum necessary dose under control of liver/kidney function.
