Researchers in China tested 25 patients suffering with psoriasis, who did not respond to western drug treatments like aminopterin, and treated them with a herbal formula. The main herbs used were Hu Zhang (Rhizoma Polygoni Cuspidati), Dan Shen (Radix Saliae Miltiorrhizae), and Jin Yin Hua (Flos Lonicerae). Out of the 25 patients, 8 were treated successfully, 8 showed moderate improvement , and 9 showed only slight improvement.