有作有止，如潮水之来，不失其期，一日一发。（热者，火也。火气所在之经，必乘本经气
旺之时而发，如心经热则潮于午，肾经热则潮于子之类，已详发热门。）若日三五发，即是发热，不名潮
热矣。潮热有虚有实，伤寒日晡潮热，胃实也，已详《伤寒论》。余症潮热，若大便
结涩，小便赤短，喜冷畏热，睡卧不安，此气盛也，参苏饮（见发热）或小柴胡汤（见寒热。）
或气乏食少，神瘁体羸，病虽暂去，而五心常有余热，此为虚，茯苓补心汤、十全
大补汤、养荣汤（二方俱见虚损）之类。病后欠调理者，八珍散。症似虚，而胸膈痞满，背
心痛，服补药不效者，痰饮也。随气而潮，故热随饮而亦潮，五饮汤。夜微热，病
人不自觉，早起动作无事，饮食如常，既无别症可疑，只是血虚，阴不济阳、宜润
补，宜上条茯苓补心等汤。脉滑有宿食，常暮发热，于伤食门求之。血虚，五心热，
夜剧者，四物二连汤。热病愈后，余热伏留在经，复发热者，小便清利，误用寒凉，
致中气虚寒，无以托邪，不能行散，大剂参、术等补之，战汗而解，血虚加归、地。
一伤感初感
伤风恶风，伤寒恶寒，犹伤酒恶酒，伤食恶食也。盖表阳被邪所郁，方欲就温
暖以宣通。故恶寒之遏闭，未发热时固恶，即发热时亦恶，不欲去衣被，甚而近火
犹凛，当暑亦恶，不论有风无风，皆生畏怯，（恶寒与恶风稍异，恶风者有风乃恶，无风则否，不
若恶寒之有风无风皆恶也。）必待表解方罢。症必发热无汗，头项强痛，脉浮紧。（所谓发热恶寒，
发于阳也。）若不发热而恶风蜷卧，则为直中阴症矣。（所谓无热恶寒，发于阴也。按《伤寒论》少阴、
厥阴篇，俱言恶寒，而太阴篇无之，阙文耳。盖六经皆有恶寒，妄生分别便非。）
一为伤寒阳邪深入
传经阳邪，深入阴分，热郁于内，表气不通，手足厥逆，恶寒，状若阴症，所
谓恶寒非寒，明是热症者此也。
一为伤寒将解
按《伤寒论·辨脉篇》曰∶脉浮而紧，按之反芤，此为本虚，故当战而汗出也。
其人本虚，是以发战，以脉浮，故当汗出而解也。若脉浮而数，按之不芤，此人本
不虚。若欲自解，但汗出耳，不发战也。盖伤寒欲解，正气实者，邪不能争，则汗
出而解，不发战。若正气本虚，邪与正争，则先战而后汗。若但内栗而汗不出，则
正气虚极，无以托邪，为危候。
一为疟疾发作
疟邪与卫气相争，正为邪滞，内郁不通，不达于表则表寒，不行于里则里亦寒，
故外战而内栗也。
发作有规律且有间歇，像潮水涨落一样，时间准确，一天发作一次。（发热，属于火邪。火邪所在的经络，必定在本经气旺盛的时候发作，比如心经有热则在午时潮热，肾经有热则在子时潮热等，这些在发热门中已经详细说明。）如果一天发作三到五次，那就只是普通的发热，不称为潮热了。潮热有虚证和实证两种。伤寒病中的日晡时（下午3-5点）潮热，是胃腑实热证，这在《伤寒论》中已有详细说明。其他病症引起的潮热，如果大便干结涩滞，小便短赤，喜欢冷饮害怕热，睡眠不安稳，这是气分盛实，可用参苏饮（见发热章节）或小柴胡汤（见寒热章节）。如果是气力匮乏、饮食减少，精神疲惫身体消瘦，虽然病症暂时缓解，但手心、脚心和心口常有余热，这属于虚证，可用茯苓补心汤、十全大补汤、养荣汤（这两个方剂都在虚损章节中列出）之类。病后缺乏调理的，用八珍散。症状看似虚证，但胸膈部痞塞胀满，背部心痛，服用补药无效的，是痰饮证。痰饮随气机流动而发作，所以热也随痰饮而潮动，用五饮汤。夜间轻微发热，病人自己感觉不到，早起活动正常，饮食如常，没有其他可疑症状，这只是血虚，阴液不能制约阳气，宜用滋润补益法，适宜用上条提到的茯苓补心汤等方剂。脉象滑利且有宿食停滞，常在傍晚发热，应在伤食门中寻求治法。血虚导致五心烦热，夜间加重的，用四物二连汤。热病痊愈后，余热伏留于经络中，再次发热的，如果小便清长通利，是因为误用了寒凉药物，导致中气虚弱寒冷，无法托举邪气外出，也不能推动邪气消散，需用大剂量人参、白术等药物补益，通过战汗的方式解除病邪，若兼有血虚则加入当归、地黄。
（轻者感到畏惧胆怯，重者出现寒战颤抖）
恶寒分为内伤所致和外感所致。
一是外感初起
伤风怕风，伤寒怕冷，就像伤酒怕酒味、伤食怕食物一样。这是因为体表的阳气被邪气郁遏，想要靠近温暖以宣通阳气。所以恶寒这种闭塞感，在未发热时固然存在，即使发热时也依然存在，不想脱去衣被，甚至靠近火源仍觉得凛冽，即使在夏天也感到畏寒，不论有无风，都会产生畏惧胆怯的感觉。（恶寒与恶风略有不同，恶风是有风时才感到不适，无风则否，不像恶寒那样无论有无风都感到不适。）必须等到表证解除才会停止。症状必然伴有发热无汗，头项强痛，脉象浮紧。（这就是所谓的“发热恶寒，发于阳经”。）如果不发热而怕风蜷缩卧倒，那就是邪气直中阴经了。（这就是所谓的“无热恶寒，发于阴经”。按《伤寒论》少阴、厥阴篇，都提到恶寒，而太阴篇没有提到，这是缺文罢了。其实六经都有可能出现恶寒，妄自区分就不对了。）
二是伤寒阳邪深入
传经而来的阳邪，深入阴分，热邪郁结在体内，表气不通畅，手足冰冷逆冷，怕冷，症状像阴证，这就是所谓的“恶寒并非真寒，明明是热证”的情况。
三是伤寒即将解除
按《伤寒论·辨脉篇》说：脉象浮而紧，按下去反而中空如葱管，这是因为本身体质虚弱，所以应当发生寒战后出汗而解。这个人本来体质虚弱，所以发生寒战，因为脉浮，所以应当通过出汗而解除病邪。如果脉象浮而数，按下去不中空，这个人本来不虚。如果想要自行解除，只会出汗而已，不会发生寒战。大概伤寒欲解时，正气充实的人，邪气不能与之抗争，就会直接出汗而解，不发生寒战。如果正气本来虚弱，邪气与正气相争，就会先寒战而后出汗。如果只是内心战栗而不出汗，那就是正气极度虚弱，无法托举邪气，属于危重证候。
四是疟疾发作
疟邪与卫气相互抗争，正气被邪气阻滞，内部郁结不通，不能通达于体表则体表发寒，不能运行于体内则体内也寒，所以外表战栗而内心恐惧。
The onset is regular with intervals, resembling the tide's ebb and flow, occurring punctually once a day. (Febrile sensation belongs to Fire pathogen. The meridian affected by Fire pathogen will manifest symptoms when its Qi is at its peak; for instance, Heart Meridian heat manifests as tidal fever at Wu hour, Kidney Meridian heat at Zi hour, etc., as detailed in the chapter on Fever.) If it occurs three to five times a day, it is merely ordinary fever, not termed tidal fever. Tidal fever can be either deficiency or excess type. In Shanghan disease, afternoon tidal fever (occurring between 3-5 PM) indicates Stomach excess heat, which is detailed in *Shanghan Lun*. For other conditions causing tidal fever: if accompanied by dry and constipated stool, scanty dark urine, preference for cold drinks, aversion to heat, and restless sleep, this indicates Qi excess; treat with Shen Su Yin (see Fever chapter) or Xiao Chai Hu Tang (see Cold and Heat chapter). If characterized by Qi deficiency, poor appetite, mental fatigue, and emaciation, where although symptoms temporarily subside, there remains residual heat in the five centers (palms, soles, and chest), this is deficiency type; treat with Fu Ling Bu Xin Tang, Shi Quan Da Bu Tang, or Yang Rong Tang (these two formulas are listed in the Deficiency Damage chapter). For post-illness lack of regulation, use Ba Zhen San. Symptoms resembling deficiency but accompanied by chest and diaphragm fullness/stuffiness, back pain, and ineffectiveness of tonifying herbs indicate Phlegm-Fluid retention. Phlegm-fluid moves with Qi, so heat also tides with fluid; treat with Wu Yin Tang. Slight night fever where the patient is unaware, normal activity upon waking, normal diet, and no other suspicious symptoms indicate Blood deficiency, where Yin fails to balance Yang; moisten and tonify using formulas like Fu Ling Bu Xin Tang mentioned above. Slippery pulse with retained food and evening fever should be sought in the Food Retention chapter. Blood deficiency causing five-center heat worsening at night is treated with Si Wu Er Lian Tang. After recovery from febrile disease, if residual heat lingers in meridians causing recurrent fever, and urination is clear and free, it is due to misusing cold-natured herbs leading to Middle Qi deficiency and cold, failing to expel pathogens; use large doses of Ginseng and Atractylodes Macrocephala Rhizome to tonify, resolving via chills-and-sweating; add Angelica Sinensis Root and Rehmannia Glutinosa Root if Blood deficiency exists.
(Light cases involve fearfulness; severe cases involve shivering.)
Aversion to cold is divided into internal injury and external contraction.
1. Initial External Contraction
Wind-strike involves aversion to wind; Cold-strike involves aversion to cold, similar to alcohol injury involving aversion to wine or food injury involving aversion to food. This is because exterior Yang is constrained by pathogens, seeking warmth to unblock and circulate. Thus, the obstruction causing aversion to cold persists before fever onset and continues during fever; patients do not wish to remove covers, and may feel chilly even near fire or in summer, experiencing fear regardless of wind presence. (Aversion to cold differs slightly from aversion to wind; aversion to wind occurs only with wind, whereas aversion to cold occurs with or without wind.) It ceases only after the exterior syndrome resolves. Symptoms must include fever, anhidrosis, stiff neck and occiput, and floating-tight pulse. (This is what is meant by "fever with aversion to cold originates from Yang.") If there is no fever but aversion to wind and curling up while lying down, it indicates direct transmission to Yin meridians. (This is what is meant by "no fever with aversion to cold originates from Yin." According to *Shanghan Lun*, Shaoyin and Jueyin chapters mention aversion to cold, but Taiyin does not, likely due to missing text. In fact, all six meridians can present aversion to cold; arbitrary distinction is incorrect.)
2. Deep Penetration of Yang Pathogens in Shanghan
Transmitted Yang pathogens penetrate deeply into Yin levels, causing heat to stagnate internally and exterior Qi to be blocked. Limbs become cold and inverted, with aversion to cold, mimicking Yin syndromes. This is the case where "aversion to cold is not true cold, but clearly a heat syndrome."
3. Resolution Phase of Shanghan
According to *Shanghan Lun · Bian Mai Pian*: "Floating and tight pulse, hollow upon pressure, indicates inherent deficiency, thus chills and sweating should occur." Since the person is inherently deficient, chills occur; due to floating pulse, sweating leads to resolution. If the pulse is floating and rapid but not hollow, the person is not inherently deficient. Spontaneous resolution involves only sweating, without chills. Generally, if Zheng Qi is strong, pathogens cannot contend, leading to sweating without chills. If Zheng Qi is weak, contention occurs, leading to chills followed by sweating. If there is inner trembling without sweating, Zheng Qi is extremely deficient and unable to expel pathogens, indicating a critical condition.
4. Malaria Paroxysm
Malaria pathogens contend with Wei Qi. Zheng Qi is obstructed by pathogens, internal stagnation prevents reaching the exterior causing exterior cold, and failure to circulate internally causes interior cold, resulting in external shivering and internal trembling.