Aldactazide (generic: spironolactone/hydrochlorothiazide) is a prescription medication used to treat fluid retention caused by congestive heart failure or other conditions. It is also used to treat high blood pressure.

Aldactazide is a single tablet containing 2 diuretics ("water pills"), spironolactone and hydrochlorothiazide. Hydrochlorothiazide (HCTZ), while increasing the removal of excess fluid, often causes low potassium levels in the blood. Spironolactone is a "potassium-sparing" diuretic which means that it works by helping the body get rid of excess fluid by increasing the amount of salt and water the kidneys remove from the blood, while still keeping potassium in the body.

Aldactazide comes in tablet form. It is usually taken once or twice daily, with or without food.

Common side effects include nausea, headache, blurred vision and dizziness. Do not drive or operate heavy machinery until you know how it affects you.