The essential mineral, Potassium, works with sodium to regulate the body's water balance.** Potassium is essential for normal fluid balance between the cells and body fluids.** Potassium is also involved in normal heart function.** In addition to Potassium Gluconate, these tablets also contain couch grass, asparagus, juniper extract, parsley, Uva Ursi, alfalfa, and buchu extract.