Aldactone controls high blood pressure. Each Aldactone 25mg tablet contains 25mg of Spironolactone. Spironolactone therefore increases the amount of salts such as sodium that they filter out of the blood and into the urine. There is excess production of Aldosterone by the adrenal glands. Aldactone can also be used for treatment of precocious puberty or myasthenia gravis. Diuretics cause your kidneys to produce more urine, you may prefer to take this medicine in the morning rather than before going to bed, as this will reduce the likelihood of you needing to get up in the night to visit the toilet. Aldactone usually is taken once a day in the morning rather than before going to bed, as this will reduce the likelihood of you needing to get up in the night to visit the toilet.