Potassium Sodium Taartrate is a double salt first prepared (in about 1675) by an apothecary, Pierre Seignette, of La Rochelle,France  As a result the salt was known as Seignette's or Rochelle salts. In medicine, this salt has been used as a mild laxative and to reduce the levels of uric acid, thus reducing inflammation and pain in gout and related conditions. Directions: One teaspoon, dissolved in half a glass of water, in the morning and at night. Warnings: Do not take if suffering from high blood pressure, heart, or kidney disease. Check with your doctor if unsure.