Spironolactone is used to prevent the potassium level from falling too low by limiting the amount of salt the body absorbs, according to Drugs.com. Spironolactone limits the amount aldosterone in the body, which is the hormone responsible for regulating the body's salt and water balance.
Spironolactone is also used to treat fluid retention in people with congestive heart failure, liver cirrhosis and nephrotic syndrome, adds Drugs.com. It is also used to combat low potassium levels in the body's bloodstream. Spironolactone can be used to treat high blood pressure, notes WebMD, which helps prevent several serious conditions, such as stroke and heart attack.
Spironolactone is typically taken by mouth. Upset stomach is a common side effect, so it is normally advised to take this medicine with food or milk. Because it can also lead to urination, people are advised to take the pill early in the day.