We made a comparative study, A patient who had suffered dizziness and ataxia took Hyungbangsabaek-san(荊防瀉白散) at first and next took Hyungbangdojeock-san(荊防導赤散). He was diagnosed as a Soyangin suffering chest knotting syndrome(結胸證) by Sasang constitutional medicine(四象醫學) and took two kinds of herbs in a row. We observed his phase of dizziness and ataxia with the conditions of stool and urine excavation, pink eye, sweating, and tongue color and tongue coating. When he took Hyungbangdojeock-san these conditions improved more than when he took the other one and his dizziness and ataxia also improved. Hyungbangdojeock-san was more useful when the severity of the disease was shallower and he had more exterior syndromes than Hyungbangsabaek-san.