古名通草。禀清秋之气，兼得土之甘淡，故其味辛甘而淡，气平味薄寒也，降
也，阳中阴也，入足少阴、太阳，亦入手少阴、太阳。能助西方秋气下降，故利小便并
专泻气滞。
木通，甘淡轻虚，上通心包，降心火，清肺热，泻小便火郁不散，利膀胱水闭不
行，消痈疽作痛，疗脾疽嗜眠，解烦哕，开耳聋，出声音，通鼻塞，行经下乳，催产堕
胎，开关导格湿热，利关节血脉，通九窍五淋，乃心胞、小肠、膀胱三经之药。凡肺受
热邪，则气化之源绝而寒水断流，宜此甘淡以助秋气下降。若君火为邪，宜用木通，相
火为邪宜用泽泻。但性寒通利，凡精滑气虚，内无湿热，并虚症孕妇，并宜忌之。
主治（痘疹合参） 利水泻火，宣通气血。凡热闭不通，心经蕴热惊悸者，泻心经
之邪热，从膀胱而出，与灯心同功。若初热时热毒下注泄泻，小水不行者，用此通导。
若难靥者，用此以利脓浆湿润之气下行。若乳母服药，须此引经。至如痘后发痈，以木
通节酒洗晒干用，亦利关节，通血脉力耳。
正禀北方水气，兼得春阳之和，故味苦咸，微寒，无毒。忌铜器。如入丸药，宜蒸
过晒干，瓦器中焙燥。
玄参，治骨蒸，散浮游之火，滋阴补肾，清利咽喉，消痰住嗽，兼能明目。治伤
寒身热支满，忽忽如不知人；疗温疟寒热往来，洒洒时常发颤。女人产乳余疾，男子骨
蒸传尸，逐肠内血瘕坚 ，散颈下痰核痈
肿，管领上下，诸气整肃而不致浊，散空中氤氲之气，肾经无根之火，惟此为最也。然
暂治有余之火则可，若欲固本滋水，则重地黄，而不及此也。至如血少目昏，停饮寒
热，血虚腹痛，脾虚泄泻，并忌之。
主治（痘疹合参） 初起热毒盛者，用以清利咽喉，并忌一切热毒痈肿，颈中痰
热，咽喉肿痛，及痘后余毒并宜。但肾经痘禁用，脾虚者忌投。
按∶玄参色黑味咸，故走肾经，故人多用以治上焦火症者，正谓水不胜火，亢而僭
上，壮水之主以制阳光。然性本寒滑，须蒸晒稍减寒性，亦不可久用也。泄泻者禁之。
【木通】
古时候称为通草。它禀受了清秋之气，又兼具土性的甘淡，所以它的味道辛、甘而淡，气性平，味薄且偏寒，性质沉降，属于阳中之阴。它入足少阴肾经和足太阳膀胱经，也入手少阴心经和手太阳小肠经。它能辅助西方秋气的下降功能，因此能利小便并专门疏通气滞。
木通，味甘淡，质地轻虚，上能通达心包络，下能降泄心火，清除肺热，泻出小便中郁结不散的火邪，通畅因水闭而不行的小便，消除痈疽引起的疼痛，治疗脾部痈疽导致的嗜睡，解除烦闷呃逆，开通耳聋，恢复声音，通鼻塞，促进月经下行及乳汁分泌，催产堕胎，开关通格以导除湿热，通畅关节血脉，通九窍及五淋，是心包络、小肠、膀胱三经的药物。凡是肺受热邪，导致气化之源断绝而寒水断流的情况，适宜用这种甘淡之品来辅助秋气下降。如果是君火为邪，适宜用木通；如果是相火为邪，则适宜用泽泻。但木通性寒且通利，凡是精气滑脱、气虚之人，体内没有湿热者，以及虚证孕妇，都应当禁忌使用。
主治（痘疹合参）：利水泻火，宣通气血。凡是热邪闭塞不通，心经蕴藏热邪导致惊悸的，可用其泻去心经的邪热，使热从膀胱排出，功效与灯心草相同。如果在初起发热时，热毒下注导致泄泻，小便不行的，用此药进行通导。如果痘疹难以结痂愈合的，用此药以利脓浆湿润之气下行。如果是乳母服药，需要此药作为引经药。至于痘后发生痈肿，用木通的节部，酒洗后晒干使用，也是利用其通畅关节、血脉的力量。
【玄参】
正禀受北方水气，又兼得春阳的和煦之气，所以味道苦咸，微寒，无毒。忌用铜器。如果用于丸药，宜蒸过后晒干，在瓦器中焙干。
玄参，治疗骨蒸劳热，散除浮游之火，滋阴补肾，清利咽喉，消痰止咳，兼能明目。治疗伤寒身热伴胸胁胀满，神情恍惚如不知人；治疗温疟寒热往来，时常战栗发抖。治疗妇女产后余疾，男子骨蒸传尸病，驱除肠内坚硬的瘀血积块，消散颈部下方的痰核痈肿，统领上下诸气使其整肃而不致浑浊，消散空中氤氲之气，对于肾经无根之火，此药最为适宜。然而，暂时治疗有余之火是可以的，如果想要固本滋水，则应重用熟地黄，而不在于此药。至于血少目昏、停饮寒热、血虚腹痛、脾虚泄泻等情况，都应当禁忌使用。
主治（痘疹合参）：痘疹初起热毒盛者，用以清利咽喉，并忌用于一切热毒痈肿、颈中痰热、咽喉肿痛，以及痘后余毒均适宜。但是肾经痘禁用，脾虚者忌投。
按语：玄参色黑味咸，所以走肾经。所以很多人用它来治上焦火症，正是所谓“水不胜火”，亢盛而上僭，通过壮水之主（滋补肾阴）来制约阳光（亢盛之火）。然而其本性寒滑，必须经过蒸晒稍减寒性，也不可以久用。泄泻者禁服。
[Mutong]
In ancient times, it was called Tongcao. It inherited the qi of clear autumn and combined with the sweet and bland nature of earth; thus, its taste is pungent, sweet, and bland, its qi is neutral, its flavor is thin, and it is slightly cold in nature. It descends and belongs to yin within yang. It enters the Foot Shaoyin (Kidney) and Foot Taiyang (Bladder) meridians, as well as the Hand Shaoyin (Heart) and Hand Taiyang (Small Intestine) meridians. It can assist the descending function of Western autumn qi; therefore, it promotes urination and specifically resolves Qi stagnation.
Mutong has a sweet and bland taste and a light, empty texture. It reaches up to pericardium, descends Heart Fire, clears Lung Heat, drains fire郁结 (stagnant fire) in urine, unblocks water closure in the bladder, eliminates pain from carbuncles and sores, treats lethargy caused by spleen carbuncles, relieves vexation and hiccups, opens deafness, restores voice, unblocks nasal congestion, promotes menstruation and lactation, induces labor and abortion, opens blockages to guide out damp-heat, unblocks joints and blood vessels, opens the nine orifices and five types of strangury. It is a herb for the Pericardium, Small Intestine, and Bladder meridians. Whenever the Lung is affected by heat pathogen, causing the source of Qi transformation to cease and cold water flow to stop, this sweet and bland herb should be used to assist the descending of autumn qi. If Ministerial Fire (Xianghuo) acts as the pathogen, Ze Xie (Alisma Rhizome) should be used. However, since Mutong is cold and purgative, it is contraindicated for those with seminal emission, Qi deficiency, internal absence of damp-heat, and pregnant women with deficiency syndromes.
Main Indications (Integration of Smallpox and Rash): Promotes urination, drains fire, and unblocks Qi and Blood. For cases of heat closure and obstruction, or Heart Meridian heat accumulation causing palpitations and fright, it drains the pathogenic heat of the Heart Meridian, allowing it to exit via the Bladder, functioning similarly to Dengxincao (Juncus Effusus Pith). In the initial stage of fever, if heat toxin sinks downward causing diarrhea and urinary retention, this herb is used for dredging. If the rash fails to crust over, it is used to facilitate the downward movement of moistening qi from pus and serum. When taken by nursing mothers, it serves as a guiding herb. Regarding post-smallpox carbuncles, the nodes of Mutong are washed with wine, dried, and used to leverage its power to unblock joints and blood vessels.
[Xuanshen]
It primarily inherits the water qi of the North and combines with the harmonious qi of spring Yang; thus, its taste is bitter and salty, slightly cold, and non-toxic. Copper vessels should be avoided. If used in pills, it should be steamed, dried, and roasted in earthenware vessels.
Xuanshen treats bone-steaming consumption, disperses floating fire, nourishes Yin and tonifies the Kidney, clears and benefits the throat, resolves phlegm and stops coughing, and also brightens the eyes. It treats Shanghan (Cold Damage) with body heat and chest/flank fullness, where the patient feels dazed as if unaware of surroundings; it treats Wen Nue (Warm Malaria) with alternating chills and fever and frequent shivering. It treats residual diseases after childbirth in women and bone-steaming infectious wasting disease in men. It drives out firm blood masses in the intestines, dissipates phlegm nodules and carbuncles under the neck, regulates Qi above and below to prevent turbidity, dissipates misty qi in the air, and is most effective for Rootless Fire in the Kidney Meridian. However, while it can temporarily treat excess fire, for consolidating the root and nourishing water, Shu Dihuang (Prepared Rehmannia Root) is heavier and more suitable than Xuanshen. It is contraindicated for scanty blood causing blurred vision, retained fluid with chills and fever, blood deficiency abdominal pain, and Spleen deficiency diarrhea.
Main Indications (Integration of Smallpox and Rash): For early-stage smallpox with abundant heat toxin, it is used to clear and benefit the throat. It is contraindicated for all heat toxin carbuncles, phlegm-heat in the neck, sore and swollen throat, and residual toxins after smallpox are suitable for treatment. However, it is forbidden for Kidney Meridian smallpox and contraindicated for Spleen deficiency.
Commentary: Xuanshen is black in color and salty in taste, so it travels to the Kidney Meridian. Therefore, many people use it to treat Upper Jiao fire syndromes, precisely addressing the concept that "Water cannot overcome Fire," leading to hyperactivity and usurping upward. By strengthening the master of Water (nourishing Kidney Yin), one controls the Solar Flare (hyperactive fire). However, its nature is inherently cold and slippery. It must be steamed and sun-dried to slightly reduce its coldness and should not be used for a long time. It is prohibited for those with diarrhea.