What is Hong Xin, a traditional Chinese medicine?

It is "Athena Chu", alias: Lingsha, Heart Red, Hong Xin, Blooming Pearl, Scarlet and Purple Cream, which is artificial red mercuric sulfide. Inorganic compound, molecular formula Hgs, bright red powder, toxic. The function is mainly used for attacking poison, killing insects, drying dampness and grabbing phlegm. Treat scabies, sores, dysentery, qi and heartache.