寒热者，证如疟状，阴阳相胜也，先寒而后热阳不足，先热而后寒阴不足，寒
多而热少，阴胜阳也，热多而寒少，阳胜阴也，寒热相半，阴阳交攻也，寒热隔日阴阳乍
离也，阳盛发热，阴盛发寒也。其有头疼汗出者，有呕吐不食者，有憎寒而饮水者，
壮热而饮汤者，有筋骨疼痛者，或泻或秘，或内寒而外热，或内热而外寒，又有寒
而腹中痛，热而腹中鸣，是有食积也。治法，因于食积者，当用白饼子下之，次行
补助，以钱氏白术散。寒多热少者小柴胡汤加桂。热多寒少者白虎汤加桂。寒热相
半者并用小柴胡汤主之。〔薛〕经曰∶阳虚则外寒，阴虚则内热，阳盛则外热，阴
盛则内寒。寒热往来，此乃阴阳相胜也，故寒气并于阴则发寒，阳气并于阳则发热，
寸口脉微为阳不足，阴气上入阳中则恶寒，尺脉弱为阴不足，阳气下入阴中则发热，
阳不足则先寒后热，阴不足则先热后寒，阴阳不归其分则寒热交争也。又上盛则发
热，下盛则发寒，阳胜则乍热，阴胜则乍寒，阴阳相胜，虚实不调，故邪气更作而
寒热往来，或乍寒乍热也。少阳胆者，肝之府，界乎太阳阳明之间，半表半里之分，
阴阳之气，易于相乘，故寒热多主肝胆经证，以小柴胡汤加减调之。若只见寒热，
起居如常，久而不愈，及大病后元气未复，悉属阴虚生热，阳虚生寒，宜用八珍汤
补之，甚者，十全大补汤。有食积为病，亦令寒热，用保和丸消之。若兼呕吐泄泻，
用六君子汤。厥冷冻饮料热，人参理中丸。作渴不止，七味白术散。食积既消，而寒热
尚作者，肝邪乘脾，所胜侮所不胜也，用异功散加柴胡、山栀。其疟证寒热，详见
疟门。
白饼子（癖） 白术散（渴） 小柴胡汤（半表半里热） 白虎汤（表里俱热）
八珍汤（虚羸） 十全大补汤（虚羸） 保和丸（宿食） 六君子汤（脾） 人参理中丸（吐
泻） 异功散（吐泻）
Cold and heat disorders present symptoms similar to malaria, resulting from the mutual excess of Yin and Yang. Chills preceding fever indicate insufficient Yang; fever preceding chills indicate insufficient Yin. More chills than fever indicates Yin excess over Yang; more fever than chills indicates Yang excess over Yin. Equal amounts of cold and heat indicate a clash between Yin and Yang. Alternating days of cold and heat indicate a sudden separation of Yin and Yang. Excess Yang causes fever; excess Yin causes chills.
Some cases are accompanied by headache and sweating; some by vomiting and inability to eat; some by aversion to cold yet desire for water; some by high fever yet desire for hot drinks; some by pain in the sinews and bones; some with diarrhea or constipation; some with internal cold and external heat; some with internal heat and external cold. Additionally, abdominal pain caused by cold and borborygmus (intestinal rumbling) caused by heat indicate food retention (accumulation of undigested food).
Treatment methods: If caused by food retention, Baibingzi (White Pill) should be used to purge, followed by tonification using Qian Yi's Baizhu San (Atractylodes Macrocephala Powder). For more chills than fever, Xiaochaihu Tang (Minor Bupleurum Decoction) with added Guizhi (Cinnamon Twig) is indicated. For more fever than chills, Baihu Tang (White Tiger Decoction) with added Guizhi (Cinnamon Twig) is indicated. For equal amounts of cold and heat, Xiaochaihu Tang (Minor Bupleurum Decoction) is the primary treatment.
[Xue Ji] stated: The *Neijing* records: "Yang deficiency leads to external cold; Yin deficiency leads to internal heat; Yang excess leads to external heat; Yin excess leads to internal cold." Alternating chills and fever results from the mutual excess of Yin and Yang. Thus, when cold Qi merges with Yin, chills occur; when Yang Qi merges with Yang, fever occurs. A faint pulse at the Cun Kou position indicates insufficient Yang, where Yin Qi enters the Yang region causing aversion to cold; a weak pulse at the Chi position indicates insufficient Yin, where Yang Qi descends into the Yin region causing fever. Insufficient Yang leads to chills first then fever; insufficient Yin leads to fever first then chills. When Yin and Yang fail to remain in their respective positions, cold and heat clash. Furthermore, excess in the upper Jiao causes fever; excess in the lower Jiao causes chills. Yang excess causes sudden fever; Yin excess causes sudden chills. Due to mutual excess of Yin and Yang and imbalance of deficiency and excess, pathogenic factors alternate, causing alternating chills and fever, or intermittent chills and fever.
The Shaoyang Gallbladder channel is the residence of the Liver, situated between the Taiyang and Yangming channels, in the half-exterior half-interior region. The Qi of Yin and Yang easily invades one another here; therefore, cold and heat disorders are primarily associated with the Shaoyang and Jueyin (Liver/Gallbladder) channels, treated with modified Xiaochaihu Tang (Minor Bupleurum Decoction). If only chills and fever are present, with normal daily activities, persisting for a long time without cure, or occurring after a severe illness when Yuan Qi has not recovered, these all belong to Yin deficiency generating heat and Yang deficiency generating cold. Bazhen Tang (Eight Treasures Decoction) should be used for tonification; for severe cases, Shiquan Dabu Tang (Ten Significant Tonifying Decoction). Food retention can also cause cold and heat, treated with Baohe Wan (Preserve Harmony Pill) to resolve stagnation. If accompanied by vomiting and diarrhea, Liujunzi Tang (Six Gentlemen Decoction) is used. For cold limbs, freezing sensation, and preference for hot drinks, Renshen Lizhong Wan (Ginseng and Poria Pill) is indicated. For unrelenting thirst, Qiwei Baizhu San (Seven-Ingredient Atractylodes Powder) is used. If food retention has been resolved but cold and heat persist, it indicates Liver pathogen attacking Spleen Earth, where the conquered element insults the conqueror; Yigong San (Extraordinary Efficacy Decoction) with added Chaihu (Bupleurum Root) and Shanzhi (Gardenia Fruit) is used. Regarding the cold and heat of malaria, see the Malaria section.
Baibingzi (for mass accumulation) Baizhu San (for thirst) Xiaochaihu Tang (for half-exterior half-interior heat) Baihu Tang (for exterior and interior heat) Bazhen Tang (for emaciation due to deficiency) Shiquan Dabu Tang (for emaciation due to deficiency) Baohe Wan (for retained food) Liujunzi Tang (for Spleen deficiency) Renshen Lizhong Wan (for vomiting and diarrhea) Yigong San (for vomiting and diarrhea)