庞安时云。尺寸俱沉者。少阴受病也。当五六日。发以其经。贯肾。络于肺系舌本。故口燥舌干而渴也。宜大承气
汤下之。补亡论常器之云。未可下也。更详余证。可下则下之。
琥按上庞氏云云。即仲景论例中语也。其用大承气汤者。又即仲景云。少阴病得之二三日。口燥咽干者。急下之。
宜大承气汤。其说同也。但一云。五六日。一云。二三日。若论传经之时。不止二三日矣。此必是口燥咽干之证。已得
之二三日。故云宜急下也。
琥又按常器之云。未可下者。以脉沉故也。殊不知少阴热病。可下之脉沉。必沉脉中兼数疾。或有力。此的系可
下之脉。昔人言不尽意。在学人以意会之而已。又少阴病。邪气传经之脉本微细。邪气入府之脉必沉实。愚尝诊之。最
为有准。
云岐子云。少阴经病。口燥舌干而渴者。胃中实热而有痛。脉沉而疾者。宜大承气汤。少阴经病。口干燥而渴。自
利清水。心下痛胃实也。脉沉而疾者。宜大承气汤。少阴经病贯肾。络于肺系舌本。故口干燥而渴。饮水。大便难者。
胃实也。脉沉而疾者。宜大承气汤。
琥按上云岐子云云。即仲景少阴病。所当急下之三证也。仲景原论中不言脉。而此独言脉。更觉详悉。
海藏老人云。少阴证口燥舌干而渴。脉尺寸俱沉。沉疾。则大承气汤。疾而无力者。不可下。如大热。而脉反细小。
不可下。宜泻心汤。
庞安时说：寸脉和尺脉都呈现沉象的，是少阴经受邪所致。通常在发病后的第五六天，病邪传变至其本经。因为少阴经脉贯穿肾脏，联络肺部，系连舌根，所以会出现口燥、舌干且口渴的症状。此时适宜使用大承气汤（峻下热结之剂）来攻下实热。
《补亡论》中常器之说：此时不可轻易攻下，需要详细审查其他证候，如果确属可下的情况，再进行攻下治疗。
王琥按：上述庞氏的说法，即出自张仲景《伤寒论》的条文示例。其中使用大承气汤的理由，又依据张仲景所说：“少阴病，得之二三日，口燥咽干者，急下之，宜大承气汤。”两者的说法是一致的。只不过庞氏说是“五六日”，而仲景说是“二三日”。如果从病邪传经的时间来看，已经不止二三日了。这必定是因为“口燥咽干”这一症状在发病后二三天内就已经出现，所以说应当紧急攻下。
王琥又按：常器之说“不可攻下”，是因为脉象沉的缘故。但他不知道，少阴热病虽然脉沉，但必须是沉脉中兼有数疾（快速），或者脉有力，这才是确实可以攻下的脉象。古人言语未尽全意，需要学习者用心领会。另外，少阴病若为邪气传经，脉象本应微细；若邪气入腑，脉象必沉实。我亲自诊察过，认为这种判断最为准确。
云岐子说：少阴经病，出现口燥、舌干且口渴，伴有胃中实热疼痛，脉象沉而疾速的，适宜用大承气汤。少阴经病，口干燥且口渴，自利清水（下利清谷），心下痛，属于胃家实，脉象沉而疾速的，适宜用大承气汤。少阴经病，经脉贯穿肾脏，联络肺部，系连舌根，所以口干燥且口渴，饮水后大便仍困难，属于胃家实，脉象沉而疾速的，适宜用大承气汤。
王琥按：上述云岐子的说法，即对应张仲景论述的少阴病应当紧急攻下的三种证候。张仲景的原论中没有提及脉象，而此处单独强调脉象，显得更加详尽完备。
海藏老人（张元素）说：少阴证出现口燥、舌干且口渴，脉象寸尺俱沉，且沉而疾速的，可用大承气汤；若脉疾而无力，则不可攻下。如果表现为大热，但脉象反而细小，也不可不攻下，适宜用泻心汤（清热燥湿、消痞散结之剂）。
Pang Anshi stated: When both the Cun (inch) and Chi (cubit) pulses are deep (Chen), it indicates that the Shaoyin (Lesser Yin) channel has been affected. Typically, on the fifth or sixth day, the pathogenic factor transmits to its originating channel. Since the Shaoyin channel penetrates the Kidney, connects with the Lung, and attaches to the root of the tongue, symptoms such as dryness of the mouth, dry tongue, and thirst arise. In such cases, Dachengqi Tang (Major Order the Qi Decoction) should be used to purge the accumulation.
Chang Qizhi, in the *Bu Wang Lun* (Supplement to Lost Chapters), remarked: Purging is not yet indicated. One must carefully examine other syndromic manifestations; if purging is indeed appropriate, then proceed with it.
Wang Hu noted: The aforementioned statement by Pang is derived from the principles found in Zhang Zhongjing's treatise. The rationale for using Dachengqi Tang aligns with Zhang Zhongjing’s assertion: "In Shaoyin disease, if after two or three days there is dryness of the mouth and throat, urgent purging is required, and Dachengqi Tang is appropriate." The theories are consistent. The discrepancy lies only in the timing: Pang mentions the fifth or sixth day, whereas Zhang mentions the second or third day. Regarding the timeline of pathogenic transmission, more than two or three days would have passed. This implies that the symptoms of dry mouth and throat had already appeared within the first two or three days of onset, hence the recommendation for urgent purging.
Wang Hu further noted: Chang Qizhi’s caution against purging stems from the observation of a deep pulse. However, he overlooked that in Shaoyin heat diseases, although the pulse may be deep, it must simultaneously exhibit rapidity (Shu) or forcefulness to be suitable for purging. Ancient texts often leave implicit meanings for students to comprehend through insight. Furthermore, in Shaoyin disease caused by pathogenic transmission through channels, the pulse is typically faint and fine (Wei Xi); however, when the pathogen enters the Fu organs, the pulse becomes deep and solid (Chen Shi). My own clinical experience confirms the accuracy of this distinction.
Yun Qizi stated: In Shaoyin channel disease, if there is dryness of the mouth, dry tongue, and thirst, accompanied by excess heat and pain in the stomach, and a pulse that is deep and rapid, Dachengqi Tang is appropriate. In Shaoyin channel disease, if there is dryness of the mouth and thirst, spontaneous diarrhea of clear water, pain in the epigastrium, indicating excess in the Stomach (Wei Shi), and a pulse that is deep and rapid, Dachengqi Tang is appropriate. In Shaoyin channel disease, since the channel penetrates the Kidney, connects with the Lung, and attaches to the root of the tongue, dryness of the mouth and thirst occur. If drinking water does not relieve constipation, indicating excess in the Stomach, and the pulse is deep and rapid, Dachengqi Tang is appropriate.
Wang Hu noted: Yun Qizi’s statements correspond to the three syndromes in Zhang Zhongjing’s work that require urgent purging in Shaoyin disease. While Zhang Zhongjing’s original text did not mention the pulse, the inclusion of pulse diagnosis here provides greater detail and completeness.
Haizang Laoren (Zhang Yuansu) stated: In Shaoyin syndrome, if there is dryness of the mouth, dry tongue, and thirst, and the pulse at both Cun and Chi positions is deep and rapid, Dachengqi Tang may be used. However, if the rapid pulse is weak and powerless, purging is contraindicated. If there is high fever but the pulse is unexpectedly fine and small, purging is also contraindicated; instead, Xiexin Tang (Drain the Epigastrium Decoction) is appropriate.