回阳为君。臣以白术培中益气。茯苓通阳化气。以助附姜峻补回阳之力。尤必佐白芍阴药以维系者。庶几阳附
于阴而内返矣。此为回阳摄阴。急救亡阳之祖方。若少阴腹痛下利。内有水气者。本方宜重用茯苓。少则六
钱。多则八钱。或一两。以通肾阳而利水。白芍宜用酒炒。以免阴凝之弊。兼咳者。加干姜八分。五味子五分
同捣如泥。以散水寒而止饮咳。下利者。去白芍。加干姜一钱。以散寒水而培脾阳。呕者。加姜半夏三钱。生
姜取汁一小匙冲。小便利者。去茯苓。以小便既利。不当更渗以竭津液也。此皆仲景治阴水症加减之成法。学
者须知同一真武汤。一治少阴误汗亡阳。一治少阴寒水洋溢。同而不同有如此。始可以用仲景之经方。
【廉勘】真武汤。加减得法。用处甚多。如俞东扶于盛暑时。以此汤治寒霍乱症。吐泻腹疼。恶寒不渴。肢冷
Aconiti Lateralis Radix Praeparata (Fuzi, 附子) and Zingiberis Rhizoma (Ganjiang, 干姜) are used as the sovereign drugs to restore yang and rescue from collapse. The minister drugs include Atractylodis Macrocephalae Rhizoma (Baizhu, 白术) to fortify the middle jiao and replenish qi, and Poria (Fuling, 茯苓) to unblock yang qi and transform qi into fluid, thereby assisting the potent effect of Fuzi and Ganjiang in vigorously tonifying and restoring yang. It is essential to add Paeoniae Radix Alba (Baishao, 白芍), a yin-nourishing herb, to anchor and preserve yin, so that yang may attach to yin and return inward. This method is termed "restoring yang to secure yin" and serves as the ancestral formula for emergency treatment of yang collapse.
In cases of Shaoyin disease presenting with abdominal pain and diarrhea accompanied by internal water retention, Poria should be heavily dosed in this formula. The dosage ranges from a minimum of six qian to a maximum of eight qian, or even one liang, to facilitate kidney yang and promote diuresis. Paeoniae Radix Alba should be stir-fried with wine to avoid its tendency to cause stagnation due to yin-cold. If cough is present, add Zingiberis Rhizoma (Ganjiang, 干姜) 8 fen and Schisandrae Fructus (Wuweizi, 五味子) 5 fen, pounded together into a paste, to disperse cold-water and stop cough caused by fluid retention. If diarrhea predominates, remove Paeoniae Radix Alba and add Zingiberis Rhizoma 1 qian to dispel cold-water and fortify spleen yang. If vomiting occurs, add Pinelliae Rhizoma Preparatum (Jiang Banxia, 姜半夏) 3 qian, mixed with 1 teaspoon of fresh Ginger Juice (Shengjiang Zhi, 生姜汁). If urination is normal, remove Poria, as excessive diuresis should be avoided when fluids are already being excreted normally to prevent depletion of body fluids. These are established modification rules from Zhang Zhongjing for treating yin-water syndromes. Practitioners must understand that although the same formula, Zhenwu Tang (True Warrior Decoction), is used, it treats either yang collapse due to erroneous sweating in Shaoyin disease or flooding of cold-water in Shaoyin disease; thus, understanding these nuances allows for the flexible application of Zhang Zhongjing's classic formulas.
[Lian Kan Commentary] When modified appropriately, Zhenwu Tang has wide applications. For instance, Yu Dongfu treated cold-type cholera during midsummer using this decoction, where symptoms included vomiting, diarrhea, abdominal pain, aversion to cold, absence of thirst, and cold limbs.