Yìzhěn yīdé 疫疹一得
Knowledge Gained on Epidemic Rashes by 余霖 (Yú Lín, zì Shīyú 師愚, 1723–1795)
About the work
The foundational mid-Qīng monograph on epidemic rash (yìzhěn 疫疹) as a clinical category, in 2 juǎn, by the Tóngchéng physician Yú Lín. Completed Qiánlóng 50 (1785), the work systematises Yú’s thirty years of clinical practice with epidemic fever — practice shaped both by the Qiánlóng jiǎshēn (1764) Tóngchéng epidemic and by the personal tragedy of his father’s death from misdiagnosed epidemic disease.
The work’s enduring contribution is doctrinal: it establishes the gypsum-centred prescription apparatus as a parallel and partial alternative to 吳有性 Wú Yǒuxìng’s dàhuáng-centred purgative protocol for wēnyì. Yú’s signature prescription, Qīngwēn bàidú yǐn 清瘟敗毒飲, combines heavy gypsum with cooling-the-blood drugs and remains one of the cornerstone prescriptions of modern TCM for severe acute febrile disease — invoked in 2003 (SARS) and 2020 (COVID-19) clinical protocols.
Abstract
The two juǎn cover: (juǎn 1) doctrinal foundation — the aetiology and clinical course of epidemic rash, with extensive discussion of qì-level versus xuè-level heat and the principle that gypsum is the irreplaceable agent for qì-level epidemic heat (“非石膏不能治熱疫” — without gypsum one cannot treat hot epidemic); (juǎn 2) the prescription apparatus, with Qīngwēn bàidú yǐn as the central prescription and elaborated modifications for compound presentations.
Yú’s doctrinal break with Wú Yǒuxìng is explicit: Wú’s framework, centred on purgation with dàhuáng, was developed for the late-Míng epidemics that killed Wú’s contemporaries; Yú argues that the mid-Qīng epidemic profile is different — the qì-level heat dominates, and gypsum is the appropriate intervention.
The Qiánlóng guǐchǒu 癸丑 (1793) Běijīng epidemic was the moment of doctrinal vindication. 紀昀 Jì Xiǎolán’s Yuèwēi cǎotáng bǐjì records that Yú’s gypsum protocol succeeded where the conventional Shānghán and Wēnyì-style treatments had failed. The same 1793 epidemic was the clinical context in which 吳塘 Wú Jūtōng made his name (see KR3eg010). The mid-Qīng wēnbìng synthesis crystallised against this shared experience.
The text was widely transmitted in the late Qīng and entered the standard wēnbìng canon — 王士雄 Wáng Mèngyīng included material from it in Wēnrè jīngwěi (KR3eg008).
Translations and research
- Hanson, Marta. Speaking of Epidemics in Chinese Medicine. Routledge, 2011 — extensive treatment of Yú Lín within the mid-Qīng wēn-bìng canon (ch. 4-5).
- Hinrichs, T. J. and Linda L. Barnes (eds.), Chinese Medicine and Healing. Harvard Belknap, 2013 — Yú as one of the mid-Qīng wēn-bìng “Four Greats” expanded to five.
- Yì-zhěn yī-dé jiào-zhù 疫疹一得校註. Beijing: Rénmín Wèishēng, modern editions.
- Wáng Wén-yuǎn 王文遠 et al., 余師愚《疫疹一得》治疫思想探析, Journal of TCM — modern doctrinal analysis.
- No standalone English translation located.
Other points of interest
The Qīngwēn bàidú yǐn prescription’s clinical use during the 2003 SARS epidemic and 2020 COVID-19 epidemic gave the Yìzhěn yīdé a remarkable second life: it is one of the small group of late-imperial Chinese medical texts whose specific prescription apparatus is still in active clinical use 250 years after composition.