Spironolactone
Spironolactone (Aldactone) is a potassium-sparing diuretic used to treat high blood pressure, heart failure and fluid retention. This page covers the Aldactone tablet range and how the medicine works.
Key points
- Spironolactone is a potassium-sparing diuretic: it removes extra fluid without flushing out potassium, unlike many other water tablets.
- In heart failure, it reduces fluid build-up, easing swelling and breathlessness.
- Aldactone is the originator brand from Pfizer; tablets come in 25mg, 50mg and 100mg strengths.
How Spironolactone works
Spironolactone blocks aldosterone, a hormone that makes the body hold on to salt and water. By blocking it, the kidneys remove extra fluid, which lowers blood pressure and reduces swelling. This is why spironolactone is used for Hypertension and Heart Failure, and for oedema, fluid retention that can cause swollen ankles, legs or abdomen. It belongs to the Heart & Blood Pressure category.
Further reading
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