煎药之法，最宜深讲，药之效不效，全在乎此。夫烹饪禽鱼羊豕，失其调度，尚能损人
，况
药专以之治病，而可不讲乎？其法载于古方之末者，种种各殊。如麻黄汤，先煎麻黄去沫，
然后加余药同煎，此主药当先煎之法也。而桂枝汤，又不必先煎桂枝，服药后，须啜热粥以
助药力，又一法也。如茯苓桂枝甘草大枣汤，则以甘澜水先煎茯苓。如五苓散，则以白饮和
服，服后又当多饮暖水。小建中汤，则先煎五味，去渣而后纳饴糖。大柴胡汤，则先煎五味
，去渣而后纳饴糖。大柴胡汤，则煎减半，去渣再煎。柴胡加龙骨牡蛎汤，则煎药成而后纳
大黄。其煎之多寡，或煎水减半，或十分煎去二三分，或止煎一二十沸，煎药之法，不可胜
者，皆各有意义。大者发散之药，及芳香之药，不宜多煎，取其生而疏荡；补益滋腻之药，
宜多煎，取其熟而停蓄。此其总诀也。故方药虽中病，而煎法失度，其药必无效。盖病家之
常服药者，或尚能根据法为之；其粗鲁贫苦之家，安能如法制度，所以病难愈也。若今之医者
，亦不能知之矣，况病家乎？
病之愈不愈，不但方必中病，方虽中病；而服之不得其法，则非特无功，而反有害，此
不可
不知也。如发散之剂，欲驱风寒出之于外，必热服，而暖覆其体，令药气行于荣卫，热气周
遍，挟风寒而从汗解。若半温而饮之，仍当风坐立，或公寂然安卧，则药留肠胃，不能得汗
，风寒无暗消之理，而荣气反为风药所伤矣。能利之药，欲其化积滞而达之于下也，必空腹
顿服，使药性鼓动，推其垢浊从大便解。若与饮食杂投，则新旧混杂，而药气与食物相乱，
则气性不专，而食积愈顽矣。故《伤寒论》等书，服药之法，宜热宜温，宜凉宜冷，宜缓宜
急，宜多宜少，宜早宜晚，宜饱宜饥，更有宜汤不宜散，宜散不宜丸，宜膏不宜圆。其轻重
大小，上下表里，治法各有当。此皆一定之至理，深思其义，必其得于心也。
煎药的方法，最值得深入探讨，药物的疗效如何，完全取决于此。烹饪禽类、鱼类、羊肉和猪肉，如果处理不当，尚且会损害人体健康，何况药物是专门用来治疗疾病的，怎能不加以研究呢？古方末尾记载的煎药方法，种类繁多，各不相同。例如麻黄汤，要先煎煮麻黄并撇去浮沫，然后再加入其余的药物共同煎煮，这是主药应当先煎的方法。而桂枝汤，则不必先煎桂枝，服药后，必须喝热粥来帮助药力发挥，这是另一种方法。又如茯苓桂枝甘草大枣汤，则用甘澜水先煎茯苓。五苓散，则用米汤调和服用，服后又应当多喝温水。小建中汤，则先煎五味子等五味药，去渣后再加入饴糖。大柴胡汤，则是先煎五味药，去渣后再加入大黄（注：原文此处有误，大柴胡汤通常无饴糖，且大黄后下或同煎视情况而定，但依原文翻译）。大柴胡汤，则是煎至药液减半，去渣后再煎。柴胡加龙骨牡蛎汤，则是煎好其他药后，再加入大黄。煎药的用水量多少，有的煎至水减半，有的煎去十分之二三分，有的只煎一二十滚，煎药的方法，数不胜数，但都各有深意。发散类的药物，以及芳香类的药物，不宜多煎，取其生性以疏泄荡涤；补益滋腻的药物，宜多煎，取其熟性以停留蓄积。这是总的诀窍。所以方药虽然对症，但如果煎法失去法度，药物必然无效。大概经常服药的病家，或许还能依据法规操作；那些粗鲁贫苦的人家，怎么能按照规范制度执行，所以疾病难以痊愈。至于现在的医生，也不能知晓这些了，何况病家呢？
疾病的痊愈与否，不仅方剂必须对症，即使方剂对症，如果服用不得其法，则不仅没有功效，反而会有害处，这是不可不知道的。如发散的药剂，想要驱赶风寒从体表排出，必须热服，并用暖物覆盖身体，使药气运行于营卫之间，热气周遍全身，挟带风寒从汗液排出。如果半温时饮用，仍然坐在风口或站立，或者静默安卧，那么药气停留在肠胃，不能出汗，风寒没有暗中消散的道理，而营气反而被风药所伤害。能通利的药物，想要化解积滞并引导其向下排出，必须空腹顿服，使药性鼓动，推动污浊之物从大便排出。如果与饮食混合服用，则新旧混杂，药气与食物相互干扰，则药性不专一，而食积更加顽固。所以《伤寒论》等书中，关于服药的方法，有宜热、宜温、宜凉、宜冷，宜缓、宜急，宜多、宜少，宜早、宜晚，宜饱、宜饥，更有宜汤剂不宜散剂，宜散剂不宜丸剂，宜膏剂不宜圆剂（注：原文“圆”通“丸”）。其轻重大小，上下表里，治法各有适宜之处。这些都是确定的至理，深思其中的含义，必定能在心中领悟。
The method of decocting herbs is worthy of deep discussion; the efficacy of medicines depends entirely on this. If poultry, fish, mutton, and pork are not cooked properly, they can still harm the human body, let alone medicinal herbs which are specifically used to treat diseases—how can we fail to study them? The methods recorded at the end of ancient prescriptions vary greatly. For instance, in Mahuang Tang (Ephedra Decoction), Ephedrae Herba (Mahuang) is boiled first, and the foam is removed before adding the remaining herbs for joint decoction; this is the method where the principal herb is decocted first. In contrast, Guizhi Tang (Cinnamon Twig Decoction) does not require boiling Cinnamomi Ramulus (Guizhi) first; after taking the medicine, one must drink hot congee to assist the medicinal power; this is another method. For example, in Fuling Guizhi Gancao Dazao Tang (Poria, Cinnamon Twig, Licorice, and Jujube Decoction), Poria (Fuling) is decocted first using Ganyan Shui (Gentle Wave Water). Wuling San (Five-Ingredient Powder with Poria) is taken mixed with Bai Yin (Rice Drink), and after ingestion, one should drink plenty of warm water. Xiao Jianzhong Tang (Minor Construct the Middle Decoction) requires decocting the five flavors (Wuwei) first, removing the dregs, and then adding Yitang (Malt Sugar). Daxiehu Tang (Major Bupleurum Decoction) involves decocting the five ingredients first, removing the dregs, and then adding Dahuang (Rhubarb). [Note: The original text repeats Daxiehu Tang but describes a different process or contains an error regarding Yitang; translating as per source] Daxiehu Tang is also described as being decocted until reduced by half, dregs removed, and then decocted again. Chaihu Jia Longgu Muli Tang (Bupleurum Plus Dragon Bone and Oyster Shell Decoction) involves adding Dahuang only after the other herbs are fully decocted. The amount of water and duration of decoction varies: some are decocted until the water is halved, some reduce by two or three-tenths, and some are boiled only for ten to twenty boils. There are countless methods of decocting, each with its own significance. Generally, dispersing herbs and aromatic herbs should not be decocted for too long, to preserve their raw nature for dispersion and purging; tonifying and cloying herbs should be decocted longer, to achieve a cooked nature that stays and accumulates. This is the general principle. Therefore, even if the prescription matches the disease, if the decoction method is improper, the medicine will certainly be ineffective. Usually, patients who take medicine frequently may follow these rules; but rough or poor households cannot adhere to such standards, which is why diseases are difficult to cure. Moreover, contemporary physicians often do not know these details, let alone the patients.
Whether a disease is cured depends not only on whether the prescription matches the disease, but also on the method of administration. Even if the prescription is correct, if taken improperly, it will not only be ineffective but also harmful. This must be understood. For dispersing agents intended to expel Wind-Cold from the exterior, they must be taken hot, and the body covered warmly to allow the medicinal qi to circulate through Ying and Wei (Nutritive and Defensive levels), spreading heat throughout the body to carry Wind-Cold out via sweating. If taken lukewarm while sitting in drafts or standing, or lying quietly without movement, the medicinal qi remains in the stomach and intestines, failing to induce sweat; Wind-Cold will not dissipate secretly, and the Ying Qi will instead be damaged by the dispersing herbs. For purgative herbs intended to resolve stagnation and guide it downward, they must be taken on an empty stomach in one dose to stimulate the medicinal action and push turbid matter out through the large intestine. If taken mixed with food, old and new contents mix, and the medicinal qi interferes with food, causing the medicinal nature to lose focus and the food stagnation to become more stubborn. Thus, in books like Shanghan Lun (Treatise on Cold Damage), methods of taking medicine include preferences for hot, warm, cool, or cold temperatures; slow or rapid intake; large or small doses; early or late timing; full or empty stomachs; and preferences for decoctions over powders, powders over pills, or pastes over pills. Their heaviness, lightness, size, upper/lower, and interior/exterior applications each have appropriate indications. These are fixed truths; by deeply contemplating their meaning, one will surely understand them internally.