典藏书目

In the initial stage of warm epidemic (Wenyi), the patient first experiences aversion to cold followed by fever. After a few days, only fever remains without aversion to cold. Within two or three days of onset, the pulse is neither floating nor deep but rapid (Shu). There is fever day and night, worsening in the late afternoon (Ribu), accompanied by headache and body pain. At this time, the pathogenic factor is located anterior to the hidden spine and posterior to the stomach and intestines. Although there are headache and body pain, these are caused by pathogenic heat floating and overflowing into the meridians. It should not be mistaken for a Taiyang exterior syndrome of Cold Damage (Shanghan); therefore, one should not arbitrarily use Ma Huang Tang (Ephedra Decoction) or Gui Zhi Tang (Cinnamon Twig Decoction) to forcibly induce sweating. Since the pathogen is not in the exterior meridians, sweating will vainly damage the defensive Qi (Wei Qi) without reducing the fever. Furthermore, purgation should not be used because the pathogen is not in the interior; purging will vainly damage Stomach Qi and worsen thirst. The appropriate treatment is Da Yuan Yin (Reach the Origin Decoction).

Da Yuan Yin Composition: Bing Lang (Arecae Semen, 2 qian), Nong Po (Magnoliae Officinalis Cortex, 1 qian), Cao Guo Ren (Tsaoko Fructus Seed, 0.5 qian), Zhi Mu (Anemarrhenae Rhizoma, 1 qian), Shao Yao (Paeoniae Radix Alba, 1 qian), Huang Qin (Scutellariae Radix, 1 qian), Gan Cao (Glycyrrhizae Radix et Rhizoma, 0.5 qian).
Take two cups of water, decoct until reduced to eight-tenths, and take warm in the afternoon.

Commentary: Bing Lang has the ability to digest and grind, eliminating latent pathogens; it is a疏利 (dispersing and promoting) herb that also removes miasma from Lingnan. Nong Po breaks up the accumulation of Li Qi (pestilential qi). Cao Guo, with its pungent, acrid, and vigorous aroma, eliminates entrenched latent pathogens. These three herbs work together to reach the nest of the pathogen, causing the pathogenic factor to collapse and quickly leave the Mo Yuan (Membrane Source). This is why it is called "Reaching the Origin." Heat injures body fluids, so Zhi Mu is added to nourish Yin; heat injures Ying Blood, so Bai Shao (White Peony Root) is added to harmonize blood; Huang Qin clears residual dry-heat; Gan Cao harmonizes the Middle Jiao. The latter four herbs are merely harmonizing agents, like drinking water when thirsty, not drugs that extract the disease. Whenever epidemic pathogens overflow into various meridians, one should add meridian-guiding herbs to assist in ascending and venting. For example, hypochondriac pain, deafness, alternating chills and fever, vomiting with bitter taste indicate pathogenic heat overflowing into the Shaoyang Meridian; add Chai Hu (Bupleuri Radix) 1 qian to this formula. If there is pain in the lower back, neck, and occiput, indicating overflow into the Taiyang Meridian, add Qiang Huo (Notopterygii Rhizoma et Radix) 1 qian. If there is eye pain, supraorbital pain, orbital pain, dry nose, and insomnia, indicating overflow into the Yangming Meridian, add Gan Ge (Puerariae Lobatae Radix) 1 qian. Cases vary in speed and severity; drug dosages vary in quantity and urgency. One must always exercise discretion based on the situation. The specified dosages are rough guidelines and should not be applied rigidly. In mild cases, the tongue coating is thin and white, fever is not severe, and the pulse is not rapid. If the pathogen does not transmit inward, one or two doses will resolve it. Slightly more severe cases must resolve through sweating. If sweating cannot occur, it is because the pathogen is entrenched in the Mo Yuan, causing separation between interior and exterior. Defensive Qi cannot penetrate inward, and Interior Qi cannot reach outward. Forced sweating is contraindicated. Some practitioners see the need for dispersing herbs and desire sweating, mistakenly using heavy blankets to obstruct or applying hot compresses/steam, which is highly inappropriate. However, at this stage of interior-exterior separation, there are no overflowing pathogens in the meridians, so the modifications for the Three Yang meridians are unnecessary; follow the original formula. In severe cases, the tongue coating resembles accumulated powder, covering the surface without gaps. After taking the decoction, if the pathogen does not resolve via sweating but sinks inward, the root of the tongue turns yellow first, gradually spreading to the center, indicating the pathogen is entering the Stomach. This indicates San Xiao Yin (Three Eliminations Decoction). If the pulse is long, surging, and rapid, with profuse sweating and extreme thirst, the pathogen has just left the Mo Yuan and desires to vent but has not yet done so; this indicates Bai Hu Tang (White Tiger Decoction). If the tongue is purely yellow with interior excess signs, the pathogen has entered the Stomach; this indicates Cheng Qi Tang (Order the Qi Decoction). Some patients may disperse and leave the Mo Yuan within two or three days; some may not transmit for half a month or more; some may appear lethargic for four or five days after onset, then suddenly intensify on the sixth day. Generally, those with strong Yuan Qi (Primal Qi) find toxins easier to transmit and transform; those with weak Yuan Qi find pathogens difficult to transform and thus difficult to transmit. If a person suffers from chronic deficiency due to other diseases and then contracts an epidemic, they can contract the pathogen but cannot transform it. How can one expect transmission? Without transmission, the pathogen is not expelled; without expulsion, the disease does not heal. Prolonged entanglement leads to deeper sinking and hiding of the pathogen, often resulting in death. Contemporary physicians mistakenly diagnose this as Deficiency Consumption (Qie Zheng) and administer Ginseng daily, causing further stagnation and consolidation of the pathogen, leading to death.