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Spironolactone

Spironolactone is a diuretic, the kind of medicine sometimes called a water tablet, and it helps the body clear excess fluid. It belongs to a class called aldosterone receptor antagonists. By removing surplus sodium and water, it eases the load that fluid build-up places on the heart and circulation.

Medicine containing Spironolactone

Aldactone

Hypertension, Oedema, Heart Failure

25 · 100mg

Spironolactone film-coated tablets under the Aldactone name are used for hypertension, oedema, heart failure and hyperaldosteronism. Several strengths and pack sizes exist. You can compare the price per tablet across options.

FromUS$0.29/ tabletView

Key points

  • Spironolactone acts on the kidneys, increasing the amount of urine passed so that surplus fluid leaves the body.
  • It holds potassium in the body while sodium and water are removed, which sets it apart from diuretics that lower potassium.
  • Its full effect develops over 2 to 4 days, and the effect lasts 2 to 3 days.

What spironolactone is used for

Spironolactone is used for hypertension and for oedema, where fluid collects in the tissues. It is also used in heart failure and in hyperaldosteronism, a condition in which the body produces too much aldosterone. Fluid retention caused by liver or kidney disease is another reason it is used, and it can be given where potassium levels are low.

How it works

Aldosterone normally signals the distal renal tubules to hold on to sodium and water. Spironolactone competes with aldosterone at those sites and blocks its effect, so more sodium and water leave the body as urine. With less fluid retained, pressure in the vessels falls and the heart has less to work against.

Forms and brands

Spironolactone is supplied as a film-coated tablet taken by mouth. Aldactone tablets contain the medicine in 25 mg and 100 mg strengths. Orders are shipped to Malaysia from pharmacy partners in India in discreet packaging.

Safety and interactions

Spironolactone is not suitable for everyone. It must not be used by anyone with a hypersensitivity to spironolactone, with Addison’s disease, with hyperkalaemia (high blood potassium) or with anuria. Potassium levels need regular blood monitoring, and excessive salt intake should be avoided. The medicine can also change how often you pass urine.

Headache, gastrointestinal upset and drowsiness are among the milder side effects. Breast enlargement in men, menstrual irregularities and hyponatraemia are moderate ones. Severe hyperkalaemia and arrhythmia are serious and require immediate medical attention.

Other medicines can matter. Potassium-sparing diuretics and ACE inhibitors are known interactions. Elderly patients need cautious use. In pregnancy, spironolactone is used only where the benefit outweighs the risk; before breastfeeding, check suitability with a qualified clinician or pharmacist.

What the sources say

  • Spironolactone caused tumours in laboratory animals, and the risks and benefits of treating a condition with it should be discussed with a doctor. (MedlinePlus)
  • Eplerenone is another aldosterone-blocking medicine, and a doctor may advise against taking spironolactone alongside it. (MedlinePlus)
  • Potassium supplements, NSAIDs such as ibuprofen and naproxen, and acetylsalicylic acid may interact with spironolactone. (MedlinePlus)

Further reading

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