← All medications

Spironolactone

Medication aldosterone antagonist heart & blood pressure
Aka: Aldactone
Brands seen in Singapore: Aldactone, Spirolon, Uractonum, Spiridon
Not medical advice. Check with your doctor or pharmacist before you start, stop or change the timing of anything you take.
How to use
What it’s for
Prescribed for fluid build-up, heart failure, blood pressure
When to take
HealthHub: morning if once daily; second dose before 6pm
Take with
Food · NHS: with food or just after food
Pros & cons
Pros
  • HealthHub: in heart failure it improves survival
  • NHS: a liquid form exists as well as tablets
  • NHS: most adults and children can take it
Cons
  • NHS: breast pain and breast growth, including in men
  • HealthHub: it raises blood potassium — tests needed
  • NHS: not usually recommended during pregnancy
Sources
  1. HSA — Listing of Registered Therapeutic Products (data.gov.sg open dataset, 5,511 rows, cached in full and filtered locally) · read 2026-08-27
    what it says
    “All 7 registered single-ingredient spironolactone products carry Forensicclassification 'Prescription Only', ATC C03DA01 — SIN02222P ALDACTONE TABLET 25 mg · SIN02153P/SIN02168P SPIROLON 25 and 100 · SIN00664P URACTONUM 25 mg · SIN16709-11P SPIRIDON 25/50/100MG.”
  2. NHS Medicines A-Z — Spironolactone: what spironolactone is for · read 2026-08-27
    what it says
    “Spironolactone is a medicine used to treat swelling caused by fluid build-up. It can also be used for high blood pressure and heart failure. It's only available with a prescription.”
  3. NHS Medicines A-Z — Spironolactone: how to take spironolactone · read 2026-08-27
    what it says
    “Spironolactone usually comes as tablets or a liquid you swallow. Your dose and how long you take it for depends on why you're taking it … take it with food or just after food”
  4. NHS Medicines A-Z — Spironolactone: side effects · read 2026-08-27
    what it says
    “Common side effects of spironolactone include: feeling dizzy; feeling sick (nausea); muscle or leg cramps; feeling tired or low in energy; breast pain and increase in breast size, including in men”
  5. NHS Medicines A-Z — Spironolactone: who can and cannot take it · read 2026-08-27
    what it says
    “You may not be able to take spironolactone if you: … have severe kidney problems; are unable to pee properly …; have Addison's disease …; have ever had high levels of potassium in your blood”
  6. NHS Medicines A-Z — Spironolactone: pregnancy and breastfeeding · read 2026-08-27
    what it says
    “Spironolactone is not usually recommended during pregnancy. This is because it can potentially affect a baby's development.”
  7. NHS Medicines A-Z — Spironolactone: taking it with other medicines · read 2026-08-27
    what it says
    “digoxin, a medicine used to treat an irregular heartbeat; some medicines to treat high blood pressure and heart failure, such as eplerenone; supplements containing potassium; non-steroidal anti-inflammatory drugs (NSAIDs), such as ibuprofen, aspirin and diclofenac”
  8. NHS Medicines A-Z — Spironolactone: food, drink and alcohol · read 2026-08-27
    what it says
    “Eating foods like bananas and avocados, or salt substitutes such as Lo-Salt, while taking spironolactone can raise potassium levels further. Ask a doctor or dietitian for advice.”
  9. HealthHub (Pharmaceutical Society of Singapore) — Spironolactone: what is this medication for · read 2026-08-27
    what it says
    “This medication is used in heart failure to improve the survival rate, reduce the symptoms of heart failure such as breathlessness or leg swelling and reduce the chance of being admitted to the hospital because of heart failure.”
  10. HealthHub — Spironolactone: how should I take or use this medication · read 2026-08-27
    what it says
    “You should take this medication with or after food. If you are taking one dose a day, take it in the morning. If you are taking the medicine two times a day, take the second dose before 6pm”
  11. HealthHub — Spironolactone: common side effects · read 2026-08-27
    what it says
    “Increased potassium levels in your blood. Your doctor may monitor your potassium levels and kidney function regularly when you are on this medication.”
  12. US FDA label for ALDACTONE (spironolactone), section 2 Dosage and Administration, via openFDA drug/label.json (effective 2025-11-28) · read 2026-08-27
    what it says
    “The recommended initial daily dose is 25 to 100 mg … Doses greater than 100 mg/day generally do not provide additional reductions in blood pressure … doses of 100 to 400 mg daily in preparation for surgery”
  13. US FDA label for ALDACTONE, section 4 Contraindications, via openFDA · read 2026-08-27
    what it says
    “ALDACTONE is contraindicated in the patients with: Hyperkalemia; Addison's disease; Concomitant use of eplerenone”
  14. US FDA label for ALDACTONE, section 7 Drug Interactions, via openFDA · read 2026-08-27
    what it says
    “Agents increasing serum potassium: Concomitant administration can lead to hyperkalemia. Lithium: Increased risk of lithium toxicity. NSAIDs: May reduce the diuretic, natriuretic and antihypertensive effect of ALDACTONE. Digoxin: ALDACTONE can interfere with radioimmunologic assays”
Report a correction View as JSON

Updated 2026-08-29. Every line above traces to a numbered source. Kozen-X is not a medical device and does not give medical advice. It lists what published sources have written down — nothing more. A pair not listed is unrecorded, not cleared. Before you start, stop or re-time anything, talk to your doctor or pharmacist.