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Ancient herbal dosage units, such as zi (1/24 liang), zhu (1/24 liang), fen (1/10 qian), and liang (37.3g in Ming dynasty), differ from modern standards. When the text mentions "one sheng" (a unit of volume), it refers to approximately one teacup today. Regarding "two zhu," six zhu equal two and a half qian, and twenty-four zhu constitute one liang. The text's mention of "three liang" corresponds to two liang today. The text's mention of "one liang" corresponds to six and a half qian today.

For powdered medicines, measurements include "daogui," "fangcunbi," and "yizhi." "Daogui" is one-tenth of a "fangcunbi." A "standard fangcunbi" is a square spoon with sides of one cun (approx. 3.3cm), used to scoop powder without spilling onto paper. "One cuo" equals four daogui; ten cuo equal one shao (spoon). "One yizhi" is equivalent to two and a half fen today, analogous to how one qian contains four characters in meaning. "Two yizhi" is half a qian, or five fen.

Regarding pill sizes: if described as size of fine hemp seeds, it refers to Sesamum indicum L. (Huma, black sesame). Similar to millet or broomcorn millet seeds, sixteen millet seeds equate to one soybean in size. Size of large hemp seeds equates to three fine hemp seeds. Size of broad beans refers to Vicia faba L. (Qubandou, green speckled bean), estimated by two large hemp seeds. Size of small beans refers to Phaseolus angularis Wight (Chixiaodou, red adzuki bean). Size of soybeans is estimated by two small beans. Size of paulownia seeds is estimated by one soybean.

When decocting liquid preparations (Tangji), the sovereign drug (Junyao) responsible for the main treatment must be boiled first for a few minutes. Then, add remaining herbs and simmer slowly over gentle heat. Do not lift the lid once the correct consistency is reached. Remove the pot and place it in cold water. Take when warm to prevent the loss of medicinal aroma and efficacy. If poured out hot while uncovered, the volatile components escape, and the drug's nature becomes incomplete. Avoid high heat during decoction, as rapid boiling consumes water quickly, preventing full extraction of medicinal properties and purity of aroma. Many households make this error yet blame the medicine for ineffectiveness; who should bear the responsibility?

For diaphoretic (sweat-inducing) formulas, boil Ephedrae Herba (Mahuang, Ephedra) for two or three boils before adding other herbs. For antihyperhidrotic (sweat-stopping) formulas, boil Cinnamon Twig Decoction ingredients (specifically Guizhi, Cinnamomi Ramulus) for two or three boils before adding others. For harmonizing formulas, boil Bupleuri Radix (Chaihu, Bupleurum) first, then add others. For warming formulas, boil Dried Ginger (Ganjiang, Zingiberis Rhizoma) first. For blood-invigorating formulas, boil Peach Kernel (Taoren, Persicae Semen) first. For diuretic formulas, boil Polyporus (Zuling, Polypori Umbellati Sclerotium) first. For antidiarrheal formulas, boil Atractylodis Macrocephalae Rhizoma (Baizhu, Atractylodes macrocephala) and Poria (Fuling, Poria cocos) first. For thirst-quenching formulas, boil Trichosanthis Radix (Tianguahua, Trichosanthes root) and Kudzu Root (Gegen, Puerariae Lobatae Radix) first. For dampness-resolving formulas, boil Atractylodis Rhizoma (Cangzhu, Atractylodes lancea) and Stephaniae Tetrandrae Radix (Fangji, Stephania tetrandra) first. For jaundice-clearing formulas, boil Yinchen (Artemisiae Scopariae Herba, Artemisia scoparia) first. For antiemetic formulas, boil Pinelliae Tuber (Banxia, Pinellia ternata) and Fresh Ginger (Shengjiang, Zingiberis Rhizoma Recens) first. For wind-dispelling formulas, boil Saposhnikoviae Radix (Fangfeng, Saposhnikovia divaricata) and Notopterygii Rhizoma et Radix (Qianghuo, Notopterygium incisum) first. For summerheat-resolving formulas, boil Moslae Herba (Xiangru, Mosla chinensis) first. For heat-clearing formulas, boil Coptidis Rhizoma (Huanglian, Coptis chinensis) first. In all treatments, the sovereign drug must be decocted first to ensure efficacy.

When using Mahuang in decoctions, remove the nodes to ensure smooth flow. Crush into bean-sized pieces. Boil separately for two or three minutes, skim off the foam on top, replenish water to original volume, then add other herbs. Failure to do so may cause irritability.

When using Rheum Palmatum (Dahuang, Rhubarb), do not grind finely. Soak in wine overnight, covered tightly. Boil next morning. Near completion, add Mangxiao (Natrii Sulfas, Mirabilite), boil for two or three minutes, then remove. This yields potent purgative effects. For pills, slight steaming prevents cold nature from damaging the stomach.

When using Donkey-hide Gelatin (Ejiao, Colla Corii Asini), Maltose (Yitang, Saccharum officinarum juice processed), or Mangxiao in decoctions, wait until the decoction is finished and dregs removed. Add these substances to the clear liquid only, boil for two or three minutes until dissolved, then pour into a cup for consumption.

When using dried Jujube (Dazao, Ziziphus jujuba), Lotus Seed (Lianzi, Nelumbinis Semen), Dried Plum Pit (Wumeiren, Prunus mume seed kernel), or Cassia Seed (Juemingzi, Cassiae Semen), split and crush them before decoction. When using Amomum fruit (Sharen, Amomi Fructus), Cardamom (Doukou, Elettaria cardamomum), or Clove (Dingxiang, Caryophylli Flos), crush them and add late in the process, boiling for a few minutes only. Otherwise, prolonged boiling dissipates their aromatic oils, reducing efficacy. When using Rhinoceros Horn (Xijiao, though now substituted by Water Buffalo Horn Shuiniu Jiaoxiao) or Antelope Horn (Lingyangjiao, Saiga Tatarica Cornu), grind into fine powder and add to the hot decoction just before taking. Alternatively, fresh grinding and decoction is acceptable. For seeds and kernels of various herbs, soak in hot water, remove skins, tips, and double-kernels. Some are stir-fried until yellow; raw ones must be crushed to release active constituents. For aromatic resins like Agarwood (Chenxiang, Aquilaria sinensis), Costus Root (Muxiang, Aucklandiae Radix), Frankincense (Ruxiang, Boswelliae Resina), and Myrrh (Moyao, Commiphora Myrrha), grind extremely fine. Pour hot decoction into a cup, mix with powder, consume, then drink the remaining liquid.

Initially, use low heat to bring water to a gentle boil. Water quantity depends on the prescription: roughly, for 24 liang of herbs, use one dou (approx. 10 liters) of water, reduce to four sheng (approx. 1.6 liters). This is the standard. However, for purgative decoctions, use less water to extract more concentrated juice (preserving raw potency). For tonic decoctions, use more water to extract less concentrated juice (allowing thorough cooking). Decoctions should be taken warm; hot liquids are easier to swallow, while cold ones may induce vomiting.