Potassium antimony tartrate, also known as tartar emetic, is used as a mordant in textile dyeing to fix dyes on natural fibers such as cotton and wool. Historically, it has been employed in electroplating baths to enhance the smoothness and hardness of metal deposits. In medicine, it served as an expectorant and treatment for parasitic infections like schistosomiasis and leishmaniasis, but its use has been largely discontinued due to toxicity and the availability of safer alternatives. In analytical chemistry, it acts as a reagent in tests for detecting arsenic (e.g., Gutzeit test) and in the preparation of standard solutions for antimony analysis; it is not typically used for sodium ion detection. Additionally, it finds limited application as a component in certain catalysts, fireproofing agents for textiles, and in the synthesis of other antimony compounds for industrial uses.