伤寒烦躁。何以明之。烦为扰扰而烦。躁为愤躁之躁。合而言之。烦躁为热也。析而
分之。烦也躁也。有阴阳之别焉。烦、阳也。躁、阴也。烦为热之轻者。躁为热之甚者。经
有烦疼、烦满、烦渴、虚烦。皆以烦为热也。有不烦而燥者。为怫怫然便作躁闷。此为
阴盛隔阳也。虽大躁欲于泥水中卧。但饮水不得入口者是矣。所谓烦躁者。谓先
烦渐至躁也。所谓躁烦者。谓先发躁而迤逦复烦者也。烦躁之由。又为不同。有邪
气在表而烦躁者。有邪气在里而烦躁者。有因火劫而烦躁者。有阳虚而烦躁者。
有阴盛而烦躁者。皆不同也。经曰。当汗不汗。其人烦躁。太阳中风。脉浮而紧。不汗
出而烦躁。大青龙汤主之者。是邪气在表而烦躁者也。病患不大便五六日。绕脐
痛。烦躁。发作有时。此有燥屎也。是邪气在里而烦躁者也。太阳病。以火熏之不得
汗。其人必躁。太阳病二日反躁。火熨其背。令人大汗出。大热入胃。躁烦者。火劫令
烦躁者也。阳微发汗。躁不得眠。与之下后复发汗。昼日烦躁不得眠。夜而安静。不
呕不渴。无表证。脉沉微。身无大热者。干姜附子汤主之者。及发汗若下之病。仍不
去烦躁者。茯苓四逆汤主之者。阳虚烦躁者也。少阴病。吐利手足冷。烦躁欲死者。
吴茱萸汤主之者。阴盛而烦躁者也。诸如此者。症之常也。非逆也。设或结胸症悉
具。烦躁者死。发热下利。厥逆。躁不得卧者死。少阴病。吐利烦躁四逆者死。少阴病。
四逆恶寒。而身蜷。脉不至。不烦而躁者死。少阴病五六日自利。复烦躁不得卧寐
者死。是数者。又皆为不治之症。呜呼。烦躁为常有之疾。复有诸不治之症。临病者
之侧。又当熟审焉。
伤寒病中的烦躁症状，该如何阐明呢？“烦”是指心中扰攘不安，“躁”是指肢体愤懑躁动。合起来说，烦躁属于热证。若分开辨析，烦和躁有阴阳的区别：烦属阳，躁属阴。烦是热邪较轻的表现，躁是热邪严重的表现。医经中有烦疼、烦满、烦渴、虚烦等记载，都是以“烦”作为热证的指征。也有不烦而表现为燥动的情况，这是患者感到怫怫然（郁热不适）随即出现躁闷，这属于阴盛格阳（阴寒内盛，逼迫阳气浮越于外）。虽然患者极度躁动想要躺在泥水中，但水却无法入口，就是这种情况。
所谓“烦躁”，是指先出现心烦，逐渐发展到肢体躁动。所谓“躁烦”，是指先出现肢体躁动，随后又转为心烦。导致烦躁的原因各不相同。有的因邪气在表而引起烦躁，有的因邪气在里而引起烦躁，有的因火疗劫迫而引起烦躁，有的因阳虚而引起烦躁，有的因阴盛而引起烦躁，这些情况都不相同。
医经说：“应当发汗而未发汗，病人出现烦躁。”又如“太阳中风证，脉象浮紧，无汗出且伴有烦躁，用大青龙汤主治”，这是邪气在表引起的烦躁。又如病人多日不大便，绕脐疼痛，烦躁，发作有时，这是体内有燥屎，属于邪气在里引起的烦躁。又如太阳病，用火熏法治疗却未能出汗，病人必然会出现躁动；太阳病第二天反而出现躁动，用火熨背部使其大汗出，导致大热入胃，引发躁烦，这是火疗劫迫导致的烦躁。
又如阳气微弱时发汗，导致躁动不得安眠；或者经过攻下后又发汗，白天烦躁不得安眠，夜间则安静，没有呕吐口渴，也没有表证，脉象沉微，身体没有大热的，用干姜附子汤主治；以及发汗或攻下后病邪未去仍见烦躁的，用茯苓四逆汤主治，这些属于阳虚引起的烦躁。又如少阴病，出现吐利、手足冰冷、烦躁欲死的症状，用吴茱萸汤主治，这是阴盛引起的烦躁。诸如此类，都是病症的常理，并非死证。
如果结胸证的症状全部具备，却出现烦躁，则是死证。发热伴下利、四肢厥冷、躁动不得卧倒的，也是死证。少阴病，出现吐利、烦躁、四肢厥逆的，是死证。少阴病，四肢厥冷、恶寒、身体蜷缩、脉搏摸不到、不烦但躁动的，是死证。少阴病五六天自下利，又出现烦躁不得卧睡的，是死证。上述几种情况，都属于不治之症。唉！烦躁虽然是常见病症，但也伴随多种不治的死证，临证诊治时必须仔细审察。
In Taiyang disease (Taiyang Disease), how should the symptoms of Fan (restlessness/distress) and Zao (agitation/restlessness) be elucidated? "Fan" refers to a state of mental disturbance and inner turmoil, while "Zao" refers to physical agitation and irritability. Taken together, Fan and Zao indicate Heat (Re). However, when analyzed separately, there is a distinction between Yin and Yang: Fan belongs to Yang, whereas Zao belongs to Yin. Fan represents a milder manifestation of Heat, while Zao indicates a more severe degree of Heat. The Classics mention conditions such as Fan pain, Fan fullness, Fan thirst, and Empty Fan (Xu Fan), all of which identify Fan as a sign of Heat. There are cases where there is no Fan but only Zao; this presents as a feeling of stifling heat followed by agitation and discomfort, which is due to Yin Excess repelling Yang (Yin Sheng Ge Yang). Although the patient may feel extreme agitation and wish to lie in mud or water, they cannot swallow water, which characterizes this condition.
The term "Fan-Zao" refers to a progression from mental distress (Fan) gradually developing into physical agitation (Zao). Conversely, "Zao-Fan" refers to initial physical agitation (Zao) that subsequently transitions back into mental distress (Fan). The causes of Fan and Zao vary. They may arise from pathogenic factors remaining in the Exterior (Biao), from pathogenic factors in the Interior (Li), from coercive fire therapy (Huo Jie), from Yang Deficiency (Yang Xu), or from Yin Excess (Yin Sheng); these etiologies are distinct.
The Classics state: "When sweating should have been induced but was not, the patient becomes restless." For instance, in Taiyang Wind Strike (Taiyang Zhong Feng), if the pulse is floating and tight, with no sweat and accompanied by restlessness and agitation, Da Qing Long Tang (Major Blue Green Dragon Decoction) is indicated; this illustrates Fan-Zao caused by pathogenic factors in the Exterior. If a patient has not had a bowel movement for five or six days, experiences periumbilical pain, restlessness, and periodic exacerbations, this indicates Dry Stool (Zao Shi) in the interior, illustrating Fan-Zao caused by pathogenic factors in the Interior.
If Taiyang Disease is treated with fire moxibustion or steaming without inducing sweat, the patient will inevitably become agitated. If on the second day of Taiyang Disease the patient paradoxically becomes agitated, and the back is steamed causing profuse sweating, leading to intense heat entering the Stomach and resulting in agitation and distress, this is Fan-Zao caused by coercive fire therapy.
If sweating is induced in a patient with weak Yang, it may lead to agitation and insomnia. If purgation is followed by sweating, the patient may experience daytime restlessness preventing sleep, while being quiet at night, without vomiting or thirst, lacking exterior signs, with a deep and faint pulse, and no significant body heat, Gan Jiang Fu Zi Tang (Dried Ginger and Aconite Decoction) is indicated. Similarly, if Fan and Zao persist despite prior sweating or purgation, Fu Ling Si Ni Tang (Poria and Four Reversals Decoction) is indicated; these represent Fan-Zao due to Yang Deficiency. In Shaoyin Disease, if vomiting, diarrhea, cold extremities, and severe restlessness occur, Wu Zhu Yu Tang (Evodia Decoction) is indicated; this represents Fan-Zao due to Yin Excess. Such cases are common manifestations of disease and do not necessarily indicate a critical prognosis.
However, if all symptoms of Jie Xiong (Chest Binding) are present along with Fan and Zao, the prognosis is fatal. If fever is accompanied by diarrhea, cold extremities (Jue Ni), and agitation preventing lying down, it is fatal. In Shaoyin Disease, if vomiting, diarrhea, restlessness, and cold extremities occur together, it is fatal. In Shaoyin Disease, if there are cold extremities, aversion to cold, curling up of the body, absent pulse, no Fan but only Zao, it is fatal. If Shaoyin Disease persists for five to six days with spontaneous diarrhea, followed by restlessness and inability to sleep, it is also fatal. These several scenarios constitute untreatable conditions. Alas! While Fan and Zao are common symptoms, they can also accompany fatal conditions; therefore, clinicians must examine them with utmost care.