Pang Anshi said: In all diseases, if there is no extreme thirst, cold water should not be administered. If there is slight thirst and dryness in the mouth and throat, small sips can be given to moisten; if there is extreme thirst with severe irritability, and the patient desires to drink one dou (a unit of volume), give five sheng (one fifth of a dou); if they desire one sheng, give half a sheng. If water is not provided, the body will become too dry to produce sweat, leading to many deaths from irritability and panting. However, do not allow the patient to drink until fully satisfied (i.e., avoid overconsumption). If profuse sweating is imminent accompanied by severe irritability and thirst, allow the patient to drink as much as they wish without hesitation. Laypeople often observe that drinking water due to thirst leads to sweating, and consequently, when patients have slight thirst, they force-feed them water, causing fluid retention. This results in many deaths from epigastric fullness, binding sensations, and panting. Those who have heat and rapid pulses, and whose conditions could still be resolved through sweating, survive only by sheer luck.

Wuling San (Five-Ingredient Powder with Poria) is used to treat patients who vomit immediately after taking medicine, or who are thirsty yet vomiting, or who remain floating in pulse and suffer from irritability and thirst after sweating, or who experience diarrhea followed by thirst and difficulty in urination, or who have fluid retention in the epigastrium due to thirst causing shortness of breath. These conditions are difficult to treat. For cases involving vomiting and difficulty in urination, Wuling San is the primary treatment.

Zhu Ling (Polyporus Umbellatus), Baizhu (Atractylodis Macrocephalae Rhizoma), Fuling (Poria), Guizhi (Cinnamomi Ramulus), Zexie (Alismatis Rhizoma) (each half liang).

Grind into fine powder, mix with rice water, and take two qian (approx. 6 grams) per dose, three times daily. Drink warm water afterwards; efficacy is achieved when sweat appears.

In Yangming disease, frequent urination leads to hard stools. Even if defecation does not occur for ten days, there is no discomfort. If the patient desires water, provide it, but rescue according to proper methods; if thirsty, Wuling San (Five-Ingredient Powder with Poria) is indicated.

In Huoluan (Cholera-like syndrome), presenting with headache, fever, and body pain, where heat predominates and there is a desire to drink water, Wuling San (Five-Ingredient Powder with Poria) is indicated. If the disease presents without fever, but with delirium, severe irritability, and spirit lacking vitality compared to normal, do not use fire therapy. Instead, administer one cun bi (approx. 3-5 grams) of Zhuling San (Polyporus Powder). Force the patient to drink one sheng (approx. 200 ml) of fresh well water, then stimulate the throat with fingers to induce vomiting. The illness will resolve promptly. If vomiting cannot be induced, do not force water intake, as fluid retention may bind in the epigastrium. Medication should be used to induce vomiting; otherwise, critical danger ensues. If vomiting is indicated but not performed, and Zhuling San is used to induce vomiting, death may occur rapidly. Acupuncture is also highly recommended. Fluid retention in the diaphragm region is extremely difficult to treat; these scenarios represent "three deaths for one life" prognosis. In Taiyang disease, after sweating, profuse sweating causes dryness in the stomach, irritability, and insomnia. If the patient desires water, provide it, but administer in small, gradual amounts until the stomach qi harmonizes and recovery occurs.