Aldactone Tablets contain the active ingredient spironolactone, which is a diuretic medication used to treat high blood pressure, heart failure, and fluid retention (edema) caused by various conditions. They work by increasing the amount of urine produced by the kidneys, which helps reduce excess fluid in the body and lower blood pressure. Aldactone Tablets may also be used to treat certain hormonal imbalances and polycystic ovary syndrome (PCOS) in women. Follow your doctor's instructions carefully when taking Aldactone Tablets for best results.