Library

There are cases of repeated exterior resolution and repeated interior purgation. Or cases where the pathogen transmits separately between the exterior and interior. Physicians who do not understand this may blame the patient for poor self-care, leading to recurrence. Patients who do not understand may blame the physician for negligent treatment, resulting in mutual resentment; both parties are mistaken. They fail to realize that this is the natural progression of the disease pattern; the nature of the pathogenic factor is such.

Shao's Commentary: Epidemic febrile diseases (Yi Zheng) are caused by turbid pathogens and aberrant qi, which lodge in the Mo Yuan (Membrane Source) and spread throughout the San Jiao (Triple Burner). The pathogen may aggregate or disperse, remain in the exterior or penetrate to the interior, without a fixed rule. Therefore, it is common to see repeated exterior resolutions, repeated interior purgations, and the reappearance of symptoms involving separate transmission between the exterior and interior. This reflects the irregularity of disease transmission and the unpredictable aggregation and dispersion of pathogens, which is the natural course of the disease, unrelated to improper treatment. However, this approach is only feasible if the patient's Yuan Qi (Primary Qi) is not deficient. For patients with a weak constitution, they may not withstand such prolonged and complicated conditions. Aside from epidemic febrile diseases, patterns such as Wind-Cold, Warmth, Summer-Heat, and Damp-Heat rarely present with such symptoms.

Exterior Resolution Followed by Interior Purgation: Initially, there are only Exterior Syndrome (Biao Zheng) manifestations without Interior Syndrome (Li Zheng) manifestations. Da Yuan Yin (Origin-Reaching Powder) is indicated. If symptoms of the Three Yang Meridians (Taiyang, Yangming, Shaoyang) are present, herbs corresponding to these meridians should be added. Subsequently, if the pulse becomes large and rapid, accompanied by spontaneous sweating and thirst, indicating that the pathogen has left the Mo Yuan but failed to exit via the exterior, Bai Hu Tang (White Tiger Decoction) should be used for acrid-cool dispersal. The pathogen resolves through sweating, and the pulse becomes calm while body temperature normalizes, leading to recovery. After two or three days, or four or five days, if fever persists, Da Yuan Yin may still be appropriate. Later, if chest fullness, abdominal distension, anorexia, irritability, and excessive thirst appear, Rhubarb (Rhei Radix et Rhizoma) should be added to purge the interior.

Shao's Commentary: Pathogens enter via the mouth and nose, first entering the Lung. Since the Lung governs the skin and hair, Exterior Syndromes appear first, manifesting as headache, body pain, fever, and aversion to cold. Da Yuan Yin is used to diffuse the pathogen. "Three Yang" refers to Taiyang, Yangming, and Shaoyang. Therefore, Notopterygium (Notopterygii Radix) is added for Taiyang, Kudzu Root (Puerariae Radix) for Yangming, and Bupleurum (Bupleuri Radix) for Shaoyang.

Interior Purgation Followed by Exterior Resolution: Initially, there is fever, which gradually progresses to a Replete Interior Syndrome (Li Zheng), resolvable by purgation. Later, fever recurs, accompanied by increased irritability, pain, heaviness of the body, and a floating pulse. Bai Hu Tang is the primary formula. If sweating does not occur, it indicates exhaustion of Body Fluids (Jin Ye); Ginseng (Ginseng Radix) should be added, and recovery follows quickly after ingestion.

Shao's Commentary: Plague pathogens enter via the mouth and nose, traveling directly along the central pathway and lodging in the Mo Yuan. The Mo Yuan is located at the half-exterior, half-interior level. As the pathogen moves from the interior to the exterior, Interior Syndromes appear first, allowing for initial purgation. After purgation, the interior becomes unobstructed, and the pathogen gradually emerges outward, affecting the Yangming Meridian. This manifests as irritability, heat, floating pulse, body pain, and heaviness. Bai Hu Tang is then used to clear the heat. Lack of sweating indicates deficiency of Righteous Qi (Zheng Qi) and depletion of fluids; Bai Hu Tang plus Ginseng is used to support the righteous Qi and expel the pathogen. If, after severe sweating and purgation, all exterior and interior syndromes resolve, followed by generalized body pain resembling being beaten with a club, and a deep, fine pulse, this is due to excessive sweating causing Yang Qi to fail to circulate uniformly, resulting in cold bones and pain. This is not an Exterior Syndrome. It requires no specific treatment; after two or three days, when Yang Qi returns, it will heal spontaneously.

Shao's Commentary: After sweating and purgation, although exterior and interior symptoms have resolved, the deficiency of fluids and weakness of Qi fails to nourish the sinews, bones, and collaterals, causing pain as if beaten. Medication should focus on nourishing Ying (Nutritive) Qi and harmonizing Yang.

Additional Commentary: Epidemic febrile diseases differ significantly from Cold Damage (Shang Han). In Cold Damage, purgation should not be performed prematurely. However, epidemic febrile diseases may present with Interior Syndromes preceding Exterior Syndromes, allowing for early purgation. Purging clears the interior and facilitates the release of the exterior. This is because epidemic pathogens move from the interior to the exterior, differing from the treatment principle of Cold Damage, which addresses the exterior before the interior. This distinction marks the clear separation between epidemic febrile diseases and Cold Damage.