Medicines & Supplements A to Z > Spironolactone


Last updated on 19/03/2021.

Overview   |   Dosage   |    Side Effects   |   Precautions  |   Tips  |   Where To Buy  

GENERIC NAME: Spironolactone


BRAND NAME(S) IN HONG KONG: Aldactone 安達通, Spironolactone Actavis

DRUG CLASS: Antihypertensive; Potassium-sparing diuretic 

USED FOR: Heart failure, edema, resistant high blood pressure, high blood levels of aldosterone 

OTHER DRUGS IN THE SAME CLASS: Amiloride, Eplerenone


What is Spironolactone for?

Spironolactone belongs to a class of medications called aldosterone antagonists (or potassium-sparing diuretics). It helps your body to get rid of salt and water more easily and also blocks the activity of male hormones (androgens). It is commonly used for swelling, liver cirrhosis, high blood pressure, high aldosterone level, heart failure with swelling and low potassium level. The anti-androgen effects of Spironolactone can be helpful in women with certain types of acne, excessive male-pattern hair growth (hirsutism), and female pattern hair loss (androgenic alopecia).

How to use it?

Spironolactone is taken by mouth.

The suggested oral dosages for different uses and age groups are listed below: 

For swelling
Adult: Take 100 mg once or twice daily.
Child: Usually 1-3 mg/kg/day every 6 to 24 hours. Doses are adjusted according to response.

For liver cirrhosis with swelling
Adult: Take 100 mg daily. Dosage ranges up to 400 mg daily.
Elderly: Start with the lowest effective dose then adjust upward if necessary.

For high aldosterone level
Adult: Start with 100-400 mg. The lowest effective dose will be given as a maintenance dose.
Child: Usually 1-3 mg/kg/day every 6 to 24 hours. Doses are adjusted according to response.
Elderly: Start with the lowest effective dose then adjust upward if necessary.

For heart failure with swelling
Adult and Elderly: Usually start with 12.5- 25 mg once daily. If 25 mg once daily dose is not tolerated, 25 mg every other day will be given.

For high blood pressure
Adults: Usually start with 25-50 mg daily. 

For women with acne, hirsutism, or androgenic alopecia
Adults: Usually start with 50-100 mg once or twice daily. Doses are adjusted based on response.

What are the side effects of Spironolactone?

The common side effects of Spironolactone are diarrhea, nausea, and high blood potassium levels. Some less common side effects include irregular menstrual bleeding, erectile dysfunction, high blood glucose level, and enlarged breasts in men.

Who should not take Spironolactone?

– People who are allergic to spironolactone or other ingredients of the formulation.
– Patients with high blood levels of potassium or Addison disease.

Pharmacist Tips:

Spironolactone can make you pass more urine. It is best to take the last dose before late afternoon, so you do not have to go to the toilet often during the night. 

Common dosing schedule:
You can take Spironolactone with or without food. However, keep it consistent. 

This schedule is for reference only, adjustments may be made according to individual needs.

Some common medications Spironolactone may interact with:
– Other blood pressure lowering medications, e.g. Lisinopril, Losartan
– Non steroidal anti-inflammatory drugs (NSAIDs), e.g. Aspirin, Diclofenac
– Potassium-containing preparations, including supplements

Please notify your doctor or pharmacist if you are taking the above medication, dosage adjustments might be needed.

Where to buy Spironolactone in Hong Kong?

In Hong Kong, Spironolactone is a prescription only medicine, and requires a prescription from a doctor to be purchased in a pharmacy. It can also be obtained from doctors. To find a pharmacy near you, refer to the list of pharmacies (“Authorized Sellers of Poisons”) from the Hong Kong Department of Health.

For more information about drug names and ingredients, you can visit Hong Kong’s Drug Office at

Need more information?

For detailed information about the use of Spironolactone in children, pregnancy and breastfeeding, and for questions about drug interactions, please check with your pharmacist or doctor.

Disclaimer: our goal is to provide you with the most relevant drug information and common dosage for Hong Kong. This information does not constitute medical advice. For specific treatment recommendations and advice, always discuss with your doctor or pharmacist, and follow the instructions included with your specific medicine.