凡煎汤剂必先以主治之为君药先煮数沸然后下余药文火缓缓熬之得所勿揭盖连罐取起坐
凉水中候温热服之庶气味不泄若据乘热揭封倾出则气泄而性不全矣煎时不宜烈火其汤腾沸耗
蚀而速涸药性未尽出而气味不纯人家多有此病而反责药不效咎将谁归
发汗药先煎麻黄二三沸后入余药同煎
止汗药先煎桂枝二三沸后下众药同煎
和解药先煎柴胡后下众药至于温药先煎干姜行血药先煎桃仁利水药先煎猪苓止泻药先煎
白术茯苓止渴药先煎天花粉干葛去湿药先煎苍术防己去黄药先煎茵陈呕吐药先煎半夏生姜风
药先煎防风羌活暑药先煎香薷热药先煎黄连凡诸治剂必有主治为君之药俱宜先煎则效自奏也
凡汤中用麻黄先另煮二三沸掠去上沫更益水如本数乃内余剂不尔令人烦
凡用大黄不须细锉先以酒浸令淹浃密覆一宿明旦煮汤临熟乃内汤中煮二三沸便起则势力
猛易得快利丸药中微蒸之恐寒伤胃也
凡汤中用阿胶饴糖芒硝皆须待汤熟起去渣只内净汁中煮二三沸熔化尽仍倾盏内服
凡汤中用完物如干枣莲子乌梅仁决明子青葙蔓荆萝卜芥苏韭等子皆劈破研碎入煎方得味
出若不碎如米之在谷虽煮之终日米岂能出哉至若桃杏等仁皆用汤泡去皮尖及双仁者或捣如泥
或炒黄色用或生用俱可
凡用砂仁豆蔻丁香之类皆须打碎迟后入药煎数沸即起不尔久久煎之其香气消散也是以效
少凡汤中用犀角羚羊角一概末如粉临服内汤中后入药一法生磨汁入药亦通
凡用沉香木香乳没一切香末药味须研极细待汤热先倾汁小盏调香末服讫然后尽饮汤药
凡煎汤药初欲微火令小沸其水数依方多少大略药二十两用水一斗煮四升以此为准然利汤
欲生少水而多取汁补汤欲熟多水而少取汁服汤宜小沸热则易下冷则呕涌
凡汤液一切宜用山泉之甘洌者次则长流河水井水不用
凡是煎煮汤剂，必须首先将作为君药的主治药物先煮沸几滚，然后再加入其余的药物，用文火慢慢熬煮，待火候适宜时不要揭开锅盖，连罐取出，放入凉水中冷却至温热后服用。这样能使药气的味道不致泄露；如果趁着热揭开封口倒出，药气就会泄露而药性就不完整了。煎药时不宜用猛火，否则药汤沸腾翻滚，会消耗侵蚀药材并迅速烧干，导致药性未能完全析出且气味不纯正。很多人家都有这种毛病，却反而责怪药无效，这责任该归咎于谁呢？
发汗药要先煎麻黄二三沸，然后加入其余药物同煎。
止汗药要先煎桂枝二三沸，然后下众药同煎。
和解药要先煎柴胡，后下众药。至于温补药要先煎干姜，行血药要先煎桃仁，利水药要先煎猪苓，止泻药要先煎白术、茯苓，止渴药要先煎天花粉、干葛，去湿药要先煎苍术、防己，退黄药要先煎茵陈，止呕药要先煎半夏、生姜，祛风药要先煎防风、羌活，解暑药要先煎香薷，清热药要先煎黄连。凡各种治疗方剂，必定有作为君药的主治药物，都应当先煎，疗效自然显现。
凡是汤剂中使用麻黄，必须先单独煮二三沸，撇去上面的浮沫，再加水恢复到原来的水量，然后放入其他药剂。如果不这样做，会让人心烦意乱。
凡是使用大黄，不需要细切，先用酒浸泡使其充分湿润，严密覆盖一夜，第二天早晨煮汤，临熟时才放入汤中煮二三沸即可起锅。这样药力猛烈，容易见效通便。如果是丸药，稍微蒸一下，恐怕寒性会伤及胃气。
凡是汤剂中使用阿胶、饴糖、芒硝，都必须等到汤煎好滤去药渣后，只将纯净的药汁倒入容器中，再放入这些药物煮二三沸使其完全熔化，然后倒入杯中服用。
凡是汤剂中使用果实类药物，如干枣、莲子、乌梅仁、决明子、青葙子、蔓荆子、萝卜子、芥子、苏子、韭菜子等，都必须劈开或研碎后入煎，才能析出味道。如果不弄碎，就像米粒在谷壳里一样，虽然煮一整天，米的味道怎么能出来呢？至于桃仁、杏仁等种子类，都用热水泡去皮尖及双仁者，或者捣成泥状，或者炒至黄色使用，或者生用都可以。
凡是使用砂仁、豆蔻、丁香之类的药物，都必须打碎，并在最后阶段加入药中，煮几沸即起。如果不这样做，长时间煎煮会使香气消散，因此疗效减少。
凡是汤剂中使用犀角、羚羊角，一律磨成粉末如面粉状，临服时放入汤中。另一种方法是现场磨汁加入药中，也是通的。
凡是使用沉香、木香、乳香、没药等一切香末类药物，必须研磨得极细，待汤热后先倒出一小杯药汁，调和香末服用完毕，然后再喝完剩下的汤药。
凡是煎汤药，起初要用微火令其小沸。水的用量依据方剂多少而定，大致原则是：药二十两用水一斗，煮取四升，以此为准。然而，用于攻下的汤剂，希望水少而取汁多；用于补益的汤剂，希望水多而取汁少。服用汤药宜小沸温热，热则容易咽下，冷则会引起呕吐反涌。
When decocting herbal medicines for liquid preparations, one must first boil the sovereign drug (the main therapeutic agent) for a few boiling periods. Subsequently, add the remaining herbs and simmer slowly over a gentle fire until properly decocted. Do not lift the lid; remove the pot from heat and place it in cool water to cool down to a warm temperature before administration. This prevents the loss of aroma and efficacy. If the lid is lifted while hot and the liquid poured out, the medicinal qi will dissipate, and the properties will be incomplete. Avoid using high heat during decoction, as vigorous boiling consumes and erodes the herbs, causing rapid evaporation. This results in incomplete extraction of medicinal properties and impure aroma. Many households suffer from this error yet blame the ineffectiveness of the medicine; who should bear the responsibility?
For diaphoretic herbs (herbs that induce sweating), such as Ephedrae Herba (Mahuang, 麻黄), boil for two or three periods first, then add other herbs to decoct together.
For antihidrotic herbs (herbs that stop sweating), such as Cinnamomi Ramulus (Guizhi, 桂枝), boil for two or three periods first, then add other herbs to decoct together.
For harmonizing herbs, such as Bupleuri Radix (Chaihu, 柴胡), boil first, then add other herbs. For warming herbs, such as Zingiberis Rhizoma (Ganjiang, 干姜), boil first. For blood-invigorating herbs, such as Persicae Semen (Taoren, 桃仁), boil first. For diuretic herbs, such as Polyporus (Zuling, 猪苓), boil first. For antidiarrheal herbs, such as Atractylodis Macrocephalae Rhizoma (Baizhu, 白术) and Poria (Fuling, 茯苓), boil first. For thirst-quenching herbs, such as Platycodonis Radix (Tianhuafen, 天花粉) and Puerariae Radix (Gegen, 干葛), boil first. For dampness-resolving herbs, such as Atractylodis Rhizoma (Cangzhu, 苍术) and Stephaniae Tetrandrae Radix (Fangji, 防己), boil first. For jaundice-clearing herbs, such as Artemisiae Scopariae Herba (Yinchen, 茵陈), boil first. For antiemetic herbs, such as Pinelliae Rhizoma (Banxia, 半夏) and Zingiberis Recens Rhizoma (Shengjiang, 生姜), boil first. For wind-dispelling herbs, such as Saposhnikoviae Radix (Fangfeng, 防风) and Notopterygii Rhizoma et Radix (Qianghuo, 羌活), boil first. For summerheat-resolving herbs, such as Elsholtziae Herba (Xiangru, 香薷), boil first. For heat-clearing herbs, such as Coptidis Rhizoma (Huanglian, 黄连), boil first. In all therapeutic formulas, the sovereign drug must be boiled first to ensure efficacy.
When using Ephedrae Herba (Mahuang, 麻黄) in decoctions, boil it separately for two or three periods, skim off the foam on the surface, add water to restore the original volume, and then add the other ingredients. Otherwise, it may cause restlessness and irritability.
When using Rhei Radix et Rhizoma (Dahuang, 大黄), there is no need to cut it finely. Soak it in wine until thoroughly moistened, cover tightly overnight, and decoct in the morning. Add it near the end of the boiling process, cook for two or three periods, and remove from heat. This method ensures potent efficacy and rapid purgative action. If used in pills, slight steaming is recommended to prevent cold nature from damaging the stomach.
When using Donkey-hide Gelatin (Ejiao, 阿胶), Maltose (Yitang, 饴糖), or Mirabilite (Mangxiao, 芒硝) in decoctions, wait until the decoction is finished and strained. Add these substances only to the clear liquid, boil for two or three periods until fully dissolved, and then pour into a cup for consumption.
When using fruit seeds in decoctions, such as Jujubae Fructus (Ganzao, 干枣), Nelumbinis Semen (Lianzi, 莲子), Pruni Semen Armeniacae Amarum (Wumeiren, 乌梅仁), Cassiae Semen (Juemingzi, 决明子), Celosiae Semen (Qingxiangzi, 青葙), Viticis Fructus (Manjingzi, 蔓荆), Raphani Semen (Luobozhongzi, 萝卜子), Sinapis Semen (Jiezi, 芥子), Perillae Fructus (Suzhongzi, 苏子), and Allii Tuberosi Semen (Jiuzhongzi, 韭子), they must be cracked or ground before decoction to release their flavors. If not crushed, like rice grains in husks, even boiling all day will not extract the essence. For kernels such as Persicae Semen (Taoren, 桃仁) and Armeniacae Semen (Xingren, 杏仁), soak in hot water, remove skins and tips, discard double-kernel varieties, crush into paste, stir-fry until yellow, or use raw, as appropriate.
When using Amomum Fructus Rotundus (Sharen, 砂仁), Cardamomi Fructus (Doukou, 豆蔻), or Ligni Aquilariae Resinatus (Dingxiang, 丁香), etc., crush them and add late in the process. Boil for a few periods and remove. Prolonged boiling dissipates their aromatic properties, reducing efficacy.
When using Cornu Bubali (Xijiao, 犀角) or Cornu Saigae Tataricae (Lingyangjiao, 羚羊角), grind them into fine powder. Add to the decoction just before administration. Alternatively, grind fresh with juice and add to the medicine; this method is also acceptable.
When using Agarwood (Chenxiang, 沉香), Costus Root (Muxiang, 木香), Olibanum (Ruxiang, 乳香), or Myrrha (Moyao, 没药), and other aromatic powders, grind them extremely fine. After the decoction is hot, pour out a small cup of the liquid, mix with the aromatic powder, consume this mixture first, and then drink the rest of the decoction.
For initial decoction, use low heat to bring the liquid to a gentle boil. Water quantity depends on the prescription: generally, for two taels of herbs, use ten dou of water, reduce to four sheng. This serves as the standard. For purgative decoctions, use less water to obtain more concentrated liquid. For tonic decoctions, use more water to obtain less concentrated liquid. Decoctions should be consumed warm; hot liquids are easier to swallow, while cold liquids may induce vomiting.
All herbal decoctions should preferably use sweet, clear spring water from mountains. Flowing river water is secondary. Well water should not be used.