1. Objectives This paper investigates the origin, the progressive changes and the constructive principles of Yangkyuksanhwa-tang (凉膈散火湯).
2. Methods Yangkyuksanhwa-tang and other related prescriptions were analyzed in terms of their pathological indications, based on previous literature including 『Donguisusebowon·Chobongwon (東醫壽世保元·草本卷)』, 『Donguisusebowon·Gabobon (東醫壽世保元·甲午本)』, 『Donguisusebowon·Sinchukbon (東醫壽世保元·辛丑本)』 and 『Dongmuyugo (東武遺稿)』.
3. Results and Conclusion 1) The Yangkyuksanhwa-tang most likely originates from Sodokeum, Yangkyuksan, Baekho-tang and Indongdeung.
2) Sodoksanhwa-tang introduced in 『Donguisusebowon·Chobongwon (東醫壽世保元·草本卷)』 progressively transformed into Chungyangsanghwa-tang (『Donguisusebowon·Gabobon (東醫壽世保元·甲午本)』) and ultimately into Yangkyuksanhwa-tang (『Donguisusebowon·Sinchukbon (東醫壽世保元·辛丑本)』), a prescription appropriate for usage in the Sangso symptomatology (上消證).
3) Yangkyuksanhwa-tang is composed of 9 herbs. Of these, Schixonepetae herba(荊芥), Ledebouriellae Radix(防風),Forsythiae fructus(連翹), Menthae Herba(薄荷), Gardeniae fructus(梔子) scatter the Hwa-qi(火氣), and Rehmanniae Radix(生地黃), Gypsum fibrosum(石膏), Anemarrhenae(知母) put off the Stomach-heat(胃熱),whereas Lonicerae caulis(忍冬藤) support the prevention of carbunculosis(癰疽).