疟者。风凉暑湿之邪。伏于血脉之中而作也。凉湿为尤重。先伤于暑湿。复伤于风凉。迫湿深入。故邪气既外
据筋络骨节之一处。而其内入者。又随血脉以上下。此血与筋骨受病之一处。相触即发病矣。血行有常度。故其发
有定时。渐早者阳气渐盛。血行渐速也。渐宴者。湿胜气困。血行渐迟也。病之轻重。在邪气之微甚。正气之强弱。
不在部位之浅深高下焉。逐日为轻。间日三日为重之说。不足据也。治法必重以破血之品。散恶血以搜伏邪。使邪
气无容藏之地。加发汗之品。使通身上下。透汗以托邪外出。虽湿彻衾褥不忌也。第其汗宜多而不宜急。急者。下
咽即汗。逆乱正气。反不能与邪相值。必下午及临卧连次服药。俟药力 百脉。半夜后接服一次。以助其力。根据
旧熟睡。于睡态朦胧之中。溱溱周浃湿散暑消百脉得鬯。汗自渐减。撤衾换衣。衣宜稍浓。仍令手足常温。微汗。
续续直过。前日发病之时。而不断也。则愈矣。伤寒论所谓先其时发汗是也。夷坚志曰。暑毒困脾。湿气连脚。不
泄则痢。不痢则疟。独炼雄黄蒸饼和药。甘草作汤。服之安乐。困脾者。困血也。连脚。故汗。必过膝也。每仿其
法。应手辄效。又吾乡俗以生鹿血酒服。截疟奇效。此固山深水寒体气所宜。热盛者未可概施。亦可见疟邪在血。
治疟之必温通血脉也。
疟疾，是由于风、凉、暑、湿等邪气，潜伏在血脉之中而引发的疾病。其中凉湿之邪尤为严重。人体先受暑湿所伤，后又受风凉所侵，迫使湿气深入体内。因此，邪气一方面停留在筋络骨节的某一部位，另一方面侵入体内的部分又随着血脉上下流动。血液与筋骨病变的部位相互接触，就会引发发病。血液运行有一定的规律，所以疟疾发作有固定的时间。发作时间逐渐提前，是因为阳气逐渐旺盛，血液运行逐渐加快；发作时间逐渐推迟（“宴”通“晏”，指晚），是因为湿气偏盛导致气机困阻，血液运行逐渐缓慢。疾病的轻重，取决于邪气的强弱和正气的盛衰，而不在于病位的浅深或高下。认为逐日发作较轻、间日或三日发作较重的说法，是不可靠的。治疗方法必须重用破血药物，消散恶血以搜剔潜伏的邪气，使邪气无处藏身；同时加入发汗药物，使全身通透出汗，将邪气托出体外。即使汗水湿透被褥也不必忌讳。只是这种汗宜多不宜急。如果发汗过急，药一下咽就大汗淋漓，会导致正气逆乱，反而不能与邪气相抗衡。必须在下午及临睡前连续服药，等待药力通达百脉，半夜后再服一次，以增强药效。患者依此法熟睡，在睡意朦胧之中，周身溱溱出汗，湿气散尽，暑热消退，百脉通畅，汗液自然逐渐减少。此时撤去被子更换衣服，衣物宜稍厚，仍让手足保持常温，微微出汗，持续不断，直到过了前一天发病的时间段，病情就会痊愈。这正是《伤寒论》所说的“在其发作之前发汗”的道理。《夷坚志》记载：暑毒困脾，湿气连及双脚，不泄泻则成痢疾，不痢疾则成疟疾。单独炼制雄黄，与蒸饼和药一起服用，再用甘草煎汤送服，服用后身体安乐。所谓“困脾”，其实是困阻血液；所谓“连脚”，是指出汗必超过膝盖。我每次仿照这种方法治疗，往往应手奏效。另外，我的家乡风俗是用生鹿血酒服用，截断疟疾疗效奇特。这固然适合山深水寒地区体质的人，但热盛者不可一概施用。这也可见疟邪在于血分，治疗疟疾必须温通血脉。
Malaria (Nüe, 疟) is a disease caused by pathogenic factors of wind (Feng, 风), cold/coolness (Liang, 凉), summerheat (Shu, 暑), and dampness (Shi, 湿) lying latent within the blood vessels (Xue Mai, 血脉). Among these, coolness and dampness are particularly severe. The body is first injured by summerheat and dampness, then subsequently injured by wind and coolness, forcing the dampness to penetrate deeply. Consequently, the pathogenic factor resides in one location involving the sinews, collaterals, bones, and joints, while the part that has entered internally travels up and down along the blood vessels. When the pathology of the blood and the sinews/bones/joints interact at this specific site, the disease manifests. Blood circulation follows a regular pattern; therefore, the onset of malaria occurs at fixed times. A gradual advancement in the time of onset indicates that Yang Qi (Yang Qi, 阳气) is gradually becoming abundant, causing blood circulation to accelerate. A gradual delay in the time of onset (Yan, 晏) indicates that dampness is predominant and Qi is constrained, causing blood circulation to slow down. The severity of the disease depends on the intensity of the pathogenic factor and the strength of the Zheng Qi (Zheng Qi, 正气), not on the superficiality or depth of the lesion. The theory that daily attacks are mild and every-other-day or three-day attacks are severe is unreliable. The treatment method must heavily utilize blood-breaking agents to dissipate evil blood and search out latent pathogens, leaving no place for the pathogen to hide. Additionally, diaphoretic agents should be added to induce thorough sweating throughout the body, pushing the pathogen out from the exterior. It is not necessary to avoid sweat soaking through the bedding. However, this sweating should be profuse rather than sudden. If sweating is too sudden, occurring immediately upon ingestion, it will cause Zheng Qi to become chaotic and unable to confront the pathogen effectively. Medication should be administered continuously in the afternoon and before sleep, allowing the medicinal power to permeate the hundred vessels (Bai Mai, 百脉). A dose should be taken again after midnight to assist the efficacy. The patient sleeps soundly according to this regimen. In the drowsy state of sleep, profuse sweating occurs all over the body, dampness dissipates, summerheat vanishes, and the hundred vessels flow freely. The sweating will naturally decrease gradually. At this point, remove the quilt and change clothes; the clothing should be slightly thicker, keeping the hands and feet warm. Maintain a slight sweating continuously without interruption until the time of the previous day's attack has passed, and the patient will recover. This corresponds to what is stated in the Shanghan Lun (Treatise on Cold Damage): "Induce sweating before the time of onset." The Yijian Zhi (Records of Yijian) states: Summer-toxin constrains the Spleen (Pi, 脾), and dampness connects to the legs. If there is no diarrhea, dysentery results; if there is no dysentery, malaria results. By refining realgar (Xionghuang, 雄黄) alone, mixing it with steamed dough pills, and taking them with Licorice Decoction (Gancao Tang, 甘草汤), one feels comfortable and safe. What is called "constraining the Spleen" actually refers to constraining the blood; what is called "connecting to the legs" means that sweating must extend past the knees. I have frequently imitated this method, and it has always been effective upon application. Furthermore, folk custom in my hometown involves drinking raw deer blood wine to arrest malaria with miraculous effect. This is indeed suitable for those with constitutions suited to deep mountains, cold water, and cold environments, but it should not be applied indiscriminately to those with excessive heat. This further demonstrates that the malaria pathogen resides in the blood, and treating malaria requires warming and unblocking the blood vessels (Xue Mai, 血脉).