小儿变蒸者，以长血气也。变者上气，蒸者体热。变蒸有轻重，其轻者，体热而微惊，
耳冷、髋亦冷，上唇头白泡起，如死鱼目珠子，微汗出，而近者五日而歇，远者八九日乃歇
；其重者，体壮热而脉乱，或汗或不汗，不欲食，食辄吐 ，无所苦也。变蒸之时，目
白睛微赤，黑睛微白，亦无所苦。蒸毕，自明了矣。
先变五日，后蒸五日，为十日之中热乃除。变蒸之时，不欲惊动，勿令旁边多人。变蒸
或早或晚，根据时如法者少也。
初变之时，或热甚者，违日数不歇，审计日数，必是为蒸，服黑散发汗；热不止者，服
紫双丸，小瘥便止，勿复服之。其变蒸之时，遇寒加之，则寒热交争，腹痛夭矫，啼不止者
，熨之则愈。
变蒸与温壮、伤寒相似，若非变蒸，身热、耳热、髋亦热，此乃为他病，可为余治；审
是变蒸，不得为余治。
其变日数，从初生至三十二日一变，六十四日再变，变且蒸；九十六日三变，一百二十
八日四变，变且蒸；一百六十日五变，一百九十二日六变，变且蒸；二百二十四日七变，二
百五十六日八变，变且蒸；二百八十八日九变，三百二十日十变，变且蒸。积三百二十日小
变蒸毕。后六十四日大蒸，后六十四日复大蒸，后百二十八日复大蒸，积五百七十六日，大
小蒸毕也。
小儿的“变蒸”现象，是为了生长血气。所谓“变”，是指上部的精气变化；所谓“蒸”，是指身体发热。变蒸有轻症和重症之分。轻症表现为身体微热且轻微惊悸，耳朵发凉、髋部也发凉，上唇边缘出现白色小泡，如同死鱼眼睛里的珠子，微微出汗，短的经过五天停止，长的经过八九天才停止；重症表现为身体高热且脉搏紊乱，有时出汗有时不出汗，不想吃东西，吃了就吐，但并没有其他痛苦。在变蒸期间，眼白部分微红，黑眼球部分微白，也没有其他痛苦。变蒸结束后，孩子自然就会变得聪明伶俐。
先经历五天的“变”，再经历五天的“蒸”，经过十天之后体内的热气才会消除。在变蒸期间，不要让孩子受到惊吓干扰，不要让旁边聚集太多人。变蒸的时间或早或晚，完全符合正常时间规律的很少。
在初次变蒸时，如果发热严重，超过了规定的天数还没有停止，仔细计算天数，确定这是变蒸反应，可以服用黑散发汗；如果发热不止，可以服用紫双丸，症状稍有好转就立即停药，不要再继续服用。如果在变蒸期间，又感受了寒邪，就会导致寒热交争，腹部疼痛剧烈扭曲，啼哭不止，用热敷的方法治疗就会痊愈。
变蒸的症状与温壮（温热病）、伤寒相似，如果不是变蒸，而是身体发热、耳朵热、髋部也热，这就是其他疾病，可以按照其他疾病进行治疗；如果确定是变蒸，就不能按照其他疾病来治疗。
关于变蒸的天数：从出生到三十二天为第一次变，六十四天为第二次变，每次都是先变后蒸；九十六天为第三次变，一百二十八天为第四次变，每次都是先变后蒸；一百六十天为第五次变，一百九十二天为第六次变，每次都是先变后蒸；二百二十四天为第七次变，二百五十六天为第八次变，每次都是先变后蒸；二百八十八天为第九次变，三百二十天为第十次变，每次都是先变后蒸。累计三百二十天，小变蒸结束。之后再过六十四天是大蒸，再过六十四天又是大蒸，再过一百二十八天还是大蒸，累计五百七十六天，大小变蒸全部结束。
The "bianzheng" (growth and transformation) in infants serves to nourish blood and qi. "Bian" refers to the transformation of upper-level essence, while "zheng" refers to bodily heat. Bianzheng varies in severity. In mild cases, there is slight fever with minor惊悸 (palpitations/fright), cold ears, and cold hips; white blisters appear on the tip of the upper lip, resembling the eyes of a dead fish; there is slight sweating, and it subsides in five days at the earliest or eight to nine days at the latest. In severe cases, there is high fever with chaotic pulse, either sweating or not sweating, anorexia, vomiting upon eating, yet without other distress. During bianzheng, the sclera may appear slightly red and the iris slightly white, but this causes no distress. After the process concludes, the infant naturally becomes alert and clear-minded.
The "bian" phase lasts for five days, followed by the "zheng" phase for five days; after ten days, the internal heat dissipates. During bianzheng, avoid startling or disturbing the child, and do not allow many people to gather nearby. The timing of bianzheng may be early or late; few cases strictly follow the standard schedule.
At the initial stage of bianzheng, if the fever is severe and does not subside within the expected number of days, carefully count the days to confirm it is indeed bianzheng. Administer Heifa San (Black Powder for Sweating) to induce sweating. If the fever persists, administer Zishuang Wan (Purple Double Pill); stop medication as soon as symptoms improve slightly, and do not continue administration. If cold pathogen invades during bianzheng, it leads to alternating chills and fever, severe abdominal pain with twisting sensations, and incessant crying; applying warm compresses will resolve the condition.
The symptoms of bianzheng resemble those of Wenzhuang (warm-heat syndrome) and Shanghan (cold damage). If it is not bianzheng, but rather characterized by body heat, hot ears, and hot hips, it is another disease and should be treated accordingly. If it is confirmed as bianzheng, it must not be treated as another disease.
Regarding the timeline: From birth to 32 days is the first bian; at 64 days is the second bian, each consisting of bian followed by zheng. At 96 days is the third bian; at 128 days is the fourth bian, each consisting of bian followed by zheng. At 160 days is the fifth bian; at 192 days is the sixth bian, each consisting of bian followed by zheng. At 224 days is the seventh bian; at 256 days is the eighth bian, each consisting of bian followed by zheng. At 288 days is the ninth bian; at 320 days is the tenth bian, each consisting of bian followed by zheng. After accumulating 320 days, the minor bianzheng cycle completes. Subsequently, after 64 days, there is a major zheng; after another 64 days, another major zheng; after another 128 days, yet another major zheng. After accumulating 576 days, both minor and major bianzheng cycles are complete.