The Effects of Xiao Xuming Decoction on Neurological Diseases
Xiao Xuming Tang (Minor Life-Extension Decoction) comes from the Beiji Qianjin Yaofang (Essential Prescriptions Worth a Thousand Gold for Emergencies). Its composition: Mahuang (Ephedrae Herba), Fangji (Stephaniae Tetrandrae Radix), Renshen (Ginseng Radix), Huangqin (Scutellariae Radix), Guixin (Cinnamomi Cortex inner portion), Gancao (Glycyrrhizae Radix), Shaoyao (Paeoniae Radix), Chuanxiong (Chuanxiong Rhizoma), Xingren (Armeniacae Semen), each one liang; Fuzi (Aconiti lateralis Radix praeparata) one piece; Fangfeng (Saposhnikoviae Radix) one and a half liang; Shengjiang (Zingiberis Rhizoma recens) five liang. Decoction method: pound the twelve herbs, add 12 sheng of water, first boil Mahuang until it boils three times, skim off the foam, add the other herbs and boil down to three sheng; divide into three doses.
Nowadays people usually decoct prepared herbal slices directly. The Tang dynasty had large and small liang units: the large liang converts to about 41.3 g today, the small liang to about 13.77 g. Here one may use the small liang; for convenience of weighing, take one liang as 14 g. Aconite varies in size; one piece generally weighs about 10-20 g, and modern pharmacies mostly use prepared aconite slices instead of whole pieces, so 15 g of aconite may be used in this formula.
The author of the Beiji Qianjin Yaofang is Sun Simiao, the Tang-dynasty physician honored by the Chinese people as the King of Medicine, with temples built in his honor across the country. Sun Simiao himself once used Xiao Xuming Tang to treat his own illness, and he held its efficacy in high regard. In the Beiji Qianjin Yaofang he states the indications of Xiao Xuming Tang as follows: "Treats sudden wind-stroke near death, body tension and relaxation alternating, crooked mouth and eyes, rigid tongue unable to speak, faintness and disorientation, oppressed and deranged spirit; all wind patterns respond when taken." He considered the formula "very effective; if not cured, prepare three or four more doses and it will surely work."
As the name suggests, Xuming Tang (Life-Extension Decoction) is a formula to save life at a critical moment. The Beiji Qianjin Yaofang contains two formulas named with "xuming": one is Xiao Xuming Tang, the other is Da Xuming San (Major Life-Extension Powder). The composition of Da Xuming San: Mahuang, Wutou (Aconiti Kusnezoffii Radix), Fangfeng, Guixin, Gancao, Shujiao (Zanthoxyli Fructus, Sichuan pepper), Xingren, Shigao (Gypsum), Renshen, Shaoyao, Danggui, Chuanxiong, Huangqin, Fuling and Ganjiang, each one liang. It treats "the eight winds and twelve bi, hemiplegia with numbness, tight and contracted hands and feet that cannot bend or extend, dizziness with inability to lift the head, unsteadiness in rising and lying down, or lying in fear as if falling, night sweating, and sexual dysfunction; women's vaginal discharge and infertility; wind entering the five zang, in severe cases with fear, many strange dreams at night, sorrowful weeping, and restless longing to run away." Its method of use differs from Xiao Xuming Tang: the herbs are ground into powder, and one fangcunbi (a spoonful about one square cun) is taken with wine twice daily; if ineffective, the dose and frequency may be slightly increased.
Comparing the major and minor Xuming formulas, we find their components similar and their indications overlapping, both related to neurological disease. Many modern neuro-degenerative and neuro-injurious diseases (such as stroke, cerebral infarction, stroke sequelae, Alzheimer's disease, hypertension, sequelae of Japanese encephalitis, Raynaud's disease and ALS) can present with the symptoms Sun Simiao described.
In fact, modern controlled clinical studies of Xiao Xuming Tang have shown it to have some efficacy against the above diseases. Some physicians have even used it for allergic rhinitis, facial neuritis, peripheral neuritis, diabetic foot, cervical spondylosis, Guillain-Barre syndrome and rheumatoid arthritis, with certain effects. But its most widespread application is in acute cerebral infarction, ischemic stroke and stroke sequelae.
Modern pharmacological research shows that Xiao Xuming Tang can improve the reduction in neuron number and the degree of white-matter lesions caused by chronic cerebral ischemia, reduce astrocyte activation, and thereby improve cerebrovascular reserve in rats with chronic cerebral ischemia. It can also lessen the mitochondrial dysfunction and structural damage caused by ischemia and hypoxia, reducing mitochondrial reactive oxygen species production and apoptosis. Studies on intracerebral hemorrhage found that Xiao Xuming Tang reduces brain edema and accelerates absorption of intracerebral hematoma. In addition, it significantly lowers cholesterol, triglycerides and low-density lipoprotein, raises high-density lipoprotein, and regulates blood lipids.
The composition of Xiao Xuming Tang is interesting; through the ages many physicians have evaluated it in much the same way, broadly regarding it as half a Mahuang Tang (Mahuang, Xingren), half a Guizhi Tang (Guixin, Shaoyao), half a Siwu Tang (Shaoyao, Chuanxiong), half a Sijunzi Tang (Renshen, Gancao), plus wind-expelling Fangfeng, damp-draining Fangji, yang-warming Fuzi and Shengjiang, and heat-clearing Huangqin. Understood by its components, this formula tonifies both qi and blood, uses cold and hot together, and treats both exterior and interior. According to traditional TCM theory, Xiao Xuming Tang therefore activates and nourishes blood, fortifies the spleen and boosts qi, expels wind and disperses cold, clears heat and fires, and drives out wind and dampness. Some criticize the formula as jumbled, yet countless patients through the ages have been treated with it for stroke and its sequelae, with many documented marked effects, and modern controlled clinical studies confirm its good efficacy.
Mahuang, Guixin and similar herbs have all been confirmed by modern pharmacology to raise blood pressure, yet there are many clinical reports that after taking Xiao Xuming Tang, patients' blood pressure fell to normal and never recurred. TCM holds that such a formula can, by expelling wind and cold, warming yang and unblocking collaterals, and activating blood and penetrating meridians, keep the body's qi and blood circulating unceasingly; modern clinical research also shows that the formula markedly improves circulation and works well against peripheral vascular disease, which may be why it lowers blood pressure.
Neuro-injurious diseases are difficult to treat, and many patients do not respond to Xiao Xuming Tang. It may be tried, but its efficacy must not be over-believed; generally, if seven doses bring not the slightest improvement, it should not be continued.