葱白（四茎） 干姜（一两，炮） 附子（一枚，炮）
少阴下利者，此方主之。
少阴属肾，水脏也，得天地闭藏之令，主禁固二便，寒邪居之，则病而失其体矣，故下
利。葱白，所以通阳气也；姜、附，所以散阴寒也。是方也，能散阴而通阳，故即葱白而名
曰白通。
葱白（四茎） 干姜（一两，炮） 附子（一枚，炮） 人尿（五合） 猪胆汁（一合）
少阴下利，脉微者，与白通汤。利不止，厥逆无脉，干呕烦者，此方主之。服汤，脉暴
出者死，微续者生。
少阴下利脉微，此少阴有真寒也，故与白通汤散阴复阳。若利不止，厥逆无脉，干呕烦
者，乃寒盛格拒乎阳，药不能达于少阴，而阳逆乱于上故也。加人尿、猪胆者，取其苦寒与
阴同类，可以引姜、附入拒格之寒而调其逆。《内经》曰∶必同其气，可使平也。正此之谓。
入
之兵也，惟明者知之。其服汤脉暴出者，正气因发泄而脱也，故死；脉微续者，阳气渐复也
，故生。
附子（二枚，炮） 茯苓（去皮） 芍药（炒，各三两） 人参（二两） 白术（四两，
炒）
少阴病口中和，背恶寒者，此方主之。少阴病身体痛，手足寒，骨节痛，脉沉者，亦此
方主之。
伤寒以阳为主，上件病皆阴胜，几于无阳矣。辛甘皆阳也，故用附、术、参、苓以养阳
；辛温之药过多，则恐有偏阳之弊，故又用芍药以扶阴。经曰∶火欲实，水当平之。此用芍
药之意也。
Scallion White (Four stems) Dried Ginger (One tael, processed) Aconite Root (One piece, processed)
When Shaoyin disease presents with diarrhea, this formula is indicated.
Shaoyin corresponds to the Kidney, which is a Water organ. It receives the mandate of closure and storage from Heaven and Earth, and governs the consolidation and control of urination and defecation. When cold pathogen occupies this area, function is impaired, leading to pathology; thus, diarrhea occurs. Scallion White serves to unblock Yang Qi; Ginger and Aconite serve to disperse Yin Cold. This formula can disperse Yin and unblock Yang; therefore, it is named Baitong Tang (White Unblocking Decoction) after the Scallion White.
Scallion White (Four stems) Dried Ginger (One tael, processed) Aconite Root (One piece, processed) Human Urine (Five he) Pig Bile (One he)
In Shaoyin disease with diarrhea and a faint pulse, administer Baitong Tang. If diarrhea persists, accompanied by cold extremities, absence of pulse, dry retching, and irritability, this formula is indicated. After taking the decoction, if the pulse suddenly emerges violently, death ensues; if the pulse gradually and slightly recovers, life is preserved.
Shaoyin disease with diarrhea and a faint pulse indicates true cold in Shaoyin; hence, Baitong Tang is given to disperse Yin and restore Yang. If diarrhea persists, accompanied by cold extremities, absence of pulse, dry retching, and irritability, it signifies that excessive cold is rejecting and repelling Yang, preventing the medicine from reaching Shaoyin, causing Yang to rebel and become chaotic above. The addition of Human Urine and Pig Bile utilizes their bitter-cold nature, which is similar to Yin, to guide Ginger and Aconite into the region where cold is rejecting, thereby regulating the rebellious Qi. The *Neijing* states: "One must align with its Qi to bring it to equilibrium." This is precisely what is meant. The subtlety here is like military strategy, known only to the wise. Regarding the pulse after taking the decoction: if it suddenly emerges violently, it indicates that healthy Qi has collapsed due to excessive discharge, leading to death; if it gradually and slightly recovers, it indicates that Yang Qi is slowly returning, leading to survival.
Aconite Root (Two pieces, processed) Poria (peeled) Peony Root (stir-fried, each three taels) Ginseng Root (two taels) Atractylodes Macrocephala Rhizome (four taels, stir-fried)
In Shaoyin disease, if the mouth feels neutral and not thirsty, and there is aversion to cold on the back, this formula is indicated. In Shaoyin disease, if there is body pain, cold hands and feet, bone and joint pain, and a deep pulse, this formula is also indicated.
In Shanghan (Cold Damage) diseases, Yang is primary. The aforementioned conditions all represent extreme excess of Yin, nearly devoid of Yang. Acrid and Sweet flavors belong to Yang; therefore, Aconite, Atractylodes, Ginseng, and Poria are used to nourish Yang. However, using too many Acrid-Warm herbs risks an imbalance favoring Yang excessively; thus, Peony Root is added to support Yin. The classics state: "If Fire desires to be substantial, Water should balance it." This explains the rationale for using Peony Root.