Diuretics

Diuretics, sometimes called "water pills", are drugs that help your body get rid of excess water and salt. If you suffer from bloating before your period and restricting your salt consuption doesn't help, your doctor may prescribe a diuretic for you. Although studies on the benefits of diuretics for premenstrual syndrome (PMS) have shown mixed results, they have been used longer in PMS treatment than any other medication. Some studies have shown diuretics to relieve symptoms, such as fatigue and depression associated with PMS.

Spironolcatone (trade name Aldactone) is a hormone that inhibits water retention. While not technically a diuretic,
it inhibits the action of the hormone that causes water retention. Physicians who use Aldactone to treat bloating associated with PMS typically prescribe 25 milligrams of spironolactone four times a day from the time of ovulation to the onset of menstruation.