杭白芍，性味苦、酸、微寒，归肝脾，功有平抑肝阳、养血敛阴、柔肝止痛，一般用于肝阴不足、肝阳上亢、血虚之证。小儿为“纯阳之体”，且“脾常不足”、“肝常有余”，与杭白芍之药性颇为相合。《幼幼集成·夜啼证治》曰：“小儿夜啼有数证：有脏寒、有心热、有神不安、有拗? Hang white peony root, bitter taste, acid, slightly cold, to the liver and spleen, power to calm the liver yang, nourishing the convergence yin, soft liver analgesia, generally used in liver deficiency, liver yang, blood deficiency card. Pediatric “pure yang body”, and “spleen often inadequate”, “liver often Yu”, and Hang Baishao quite similar drug. “Young and children integrated nightingale card rule” said: "Pediatric Yeti card: there is dirty cold, warm heart, uneasy, with a bend?