Potassium sodium tartrate tetrahydrate has been used medicinally as a laxative. It has also been used in the process of silvering mirrors. It is an ingredient of Fehling's solution (reagent for reducing sugars). It is used in electroplating, in electronics and piezoelectricity, and as a combustion accelerator in cigarette paper (similar to an oxidizer in pyrotechnics).In organic synthesis, it is used in aqueous workups to break up emulsions, particularly for reactions in which an aluminium-based hydride reagent was used. Sodium Potassium tartrate is also important in the food industry.