Spironolactone oral

Therapeutic action

Potassium-sparing diuretic, antagonist of aldosterone.

Indications

Oedema associated with heart failure, hepatic cirrhosis, and nephrotic syndrome.

Forms and strengths

• 25 mg tablet.

Dose

When weight is stable, administer the lowest possible maintenance dose in order to prevent adverse effects.

The daily dose can be administered in 2 to 3 divided doses or once daily.

Duration

According to clinical response; avoid prolonged use.

Contra-indications, adverse effects, precautions

• Do not administer to patients with severe renal impairment, anuria, hyperkalaemia above 5 mmol/litre, or hyponatraemia.
• Do not combine with potassium salts, potassium-sparing diuretics, or lithium.
• Avoid or closely monitor combination with angiotensin-converting enzyme inhibitors and digoxin and reduce dosages as needed.
• May cause hyperkalaemia, hyponatraemia, metabolic acidosis in decompensated cirrhosis, gynecomastia, metrorrhagia, impotence, amenorrhoea, gastrointestinal disturbances, headache, skin rash, and drowsiness.
• Administer with caution in patients with hepatic impairment, renal impairment, or diabetes.
• Monitor plasma potassium levels regularly.
• Pregnancy: avoid and use only if clearly needed; spironolactone is not indicated in the treatment of pregnancy-related oedema.
• Breast-feeding: no contra-indication.
• In children with oedema, the daily dose is 1 to 3 mg/kg once daily or 0.5 to 1.5 mg/kg 2 times daily.