【气味】
苦寒无毒。沉而降。阴中之阴也。（酒浸入太阳经。酒洗炒入阳明经。余经生用。）
【主治】
走而不守。泻诸实热。大肠不通。荡涤肠胃间热。除下焦湿。推陈致新。消宿食。
破女子瘕症。下痢赤白。里急腹痛。仲景泻心汤。专治心气不足。吐血衄血之症。或以为心
气不足法当用补。反以苦寒泻之者何也。不知真心不足者。必不吐衄兼之吐血。此则本经之
阳亢甚无辅。以致阴血妄行飞越。故宜用大黄以泻去亢甚之火。使之和平。则血归经而自安
也。又言大黄泻心实。泻四经血分中之邪火者何义。盖少阴心经之阴气不足。则心火燔灼。
邪气乘虚结于上焦。胃之上脘在于心。故曰泻心实泻脾胃也。又心之阴气。不足。渐渍既久
。则肺与肝俱各受火而病作。用黄芩佐大黄以救肺。用黄连佐大黄以救肝。肺为阴之主。肝
为阴之母。血之舍肝。肺之火既退。阴血自复其旧。故曰泻心实泻肝肺也。凡病在气分。及
胃寒血虚并妊娠产后。慎勿轻用。轻用之恐伤元气。耗阴血。
【气味】
苦辛温无毒。沉而降。阴也。入厥阴少阳经。治肝胆之病。
【主治】
气滞。下食破积结。祛下焦诸湿。疗左胁肝经积气。小腹疝痛。消乳肿。青皮汤用
之以治久疟热甚致结癖块之症。盖疏利肝邪。削其坚实也。但有滞气则破滞气。无滞气则损
真气。不可不慎择而用之也。又曰青皮炒黑可入血分。青皮亦能发汗。有汗者不可用。
【气味】
味苦，性寒，无毒。药性沉降，属于阴中之阴。（用酒浸泡可入太阳经；用酒洗后炒制可入阳明经；其他经络则生用。）
【主治】
药性走窜而不守静。能泻除各种实热证。治疗大肠传导失司导致的便秘。荡涤肠胃之间的积热。清除下焦的湿气。推陈出新（去除陈旧之物，促进新生）。消除停滞的食物。
破除女性腹中的癥瘕积聚。治疗痢疾，大便中带有红色和白色黏液。伴有里急后重和腹部疼痛。张仲景的泻心汤，专门治疗心气不足引起的吐血、鼻衄症状。有人疑惑：既然认为是心气不足，按照法则应当使用补法，为什么反而用苦寒的药物来泻呢？这是因为不知道真正的真心气虚，必然不会同时出现吐血，而且伴随吐血的情况，这其实是本经阳气亢盛至极且缺乏辅佐，导致阴血妄行飞越。因此适宜使用大黄来泻去亢盛的火热，使气血恢复平和，血液回归经脉自然安宁。又说大黄能“泻心实”，并泻除四经血分中的邪火，这是什么道理呢？大概是因为少阴心经的阴气不足，导致心火燔灼。邪气乘虚结聚于上焦，胃的上脘部位与心相关联，所以说“泻心实”实际上就是“泻脾胃”。另外，心的阴气不足，浸渍日久，肺和肝都会受到火邪侵害而发病。用黄芩辅助大黄以救肺，用黄连辅助大黄以救肝。肺是阴的主宰，肝是阴的母亲，血舍于肝。肺的火邪退去后，阴血自然恢复常态，所以说“泻心实”实际上就是“泻肝肺”。凡是病在气分，以及胃寒、血虚和妊娠产后期间，切勿轻易使用。如果轻率使用，恐怕会损伤元气，耗竭阴血。
【气味】
味苦辛，性温，无毒。药性沉降，属于阴。入厥阴经和少阳经。治疗肝胆的疾病。
【主治】
治疗气机阻滞。下行食物，破除积结。祛除下焦的各种湿邪。治疗左侧胁肋部肝经的积气。小腹部疝气疼痛。消除乳房肿胀。青皮汤中使用青皮，来治疗久疟疾热势严重导致形成癖块的症状。这大概是疏利肝邪，削伐其坚实之积。但是，如果有滞气就破除滞气，如果没有滞气就会损伤真气，不可不谨慎选择使用。又说青皮炒黑后可以入血分。青皮也能发汗，有汗出症状者不可使用。
[Flavor and Nature]
Bitter, cold, non-toxic. The action is descending, belonging to Yin within Yin. (Soaked in wine, it enters the Taiyang Meridian; washed with wine and stir-fried, it enters the Yangming Meridian; for other meridians, it is used raw.)
[Indications]
It moves freely without staying fixed. It purges various excess heat syndromes. It treats constipation due to large intestine dysfunction. It sweeps away heat accumulated in the intestines and stomach. It eliminates dampness in the lower Jiao. It promotes the elimination of the old and the generation of the new. It resolves retained food.
It breaks up masses (zheng) in women. It treats dysentery with red and white discharge. It addresses tenesmus and abdominal pain. In Zhang Zhongjing's Xiexin Tang (Heart-Purging Decoction), it is specifically indicated for hematemesis and epistaxis caused by "heart Qi deficiency." One might ask: if heart Qi deficiency is diagnosed, the principle dictates using tonification; why use bitter-cold purgatives instead? This misunderstanding arises from not realizing that true deficiency of the Heart's original Qi would not present with hematemesis accompanied by epistaxis. In this case, the Yang of the meridian is hyperactive to an extreme degree without sufficient support, causing Yin blood to act recklessly and fly out of its vessels. Therefore, Dahuang (Rhei Radix et Rhizoma) should be used to purge the hyperactive fire, restoring harmony so that the blood returns to its vessels and calms down. Furthermore, it is said that Dahuang purges "Heart Excess" and clears pathogenic fire from the blood aspect of the four meridians. What is the meaning of this? Generally, when the Yin Qi of the Shaoyin Heart Meridian is insufficient, Heart Fire blazes fiercely. Pathogenic factors take advantage of the deficiency to knot in the Upper Jiao. The upper part of the Stomach is connected to the Heart; thus, "purging Heart Excess" essentially means "purging the Spleen and Stomach." Additionally, prolonged insufficiency of Heart Yin causes the Lungs and Liver to suffer from fire, leading to disease. Huangqin (Scutellariae Radix) assists Dahuang to rescue the Lung; Huanglian (Coptidis Rhizoma) assists Dahuang to rescue the Liver. The Lung is the master of Yin; the Liver is the mother of Yin. Blood resides in the Liver. Once the fire in the Lung recedes, Yin blood naturally restores its former state. Thus, "purging Heart Excess" essentially means "purging the Liver and Lung." For diseases located in the Qi aspect, as well as cases of Stomach Cold, Blood Deficiency, pregnancy, and postpartum periods, one must be cautious and not use it lightly. Indiscriminate use may damage Yuan Qi (Original Qi) and consume Yin blood.
[Flavor and Nature]
Bitter and acrid, warm, non-toxic. The action is descending, belonging to Yin. It enters the Jueyin and Shaoyang Meridians. It treats diseases of the Liver and Gallbladder.
[Indications]
It treats Qi stagnation. It directs food downward and breaks up accumulations. It dispels various dampness in the lower Jiao. It treats stagnant Qi in the Liver Meridian located in the left hypochondrium. It treats hernia pain in the lower abdomen. It reduces breast swelling. In Qingpi Tang (Green Peel Decoction), Qingpi (Aurantii Fructus Immaturus) is used to treat conditions where chronic malaria with severe heat leads to the formation of mass-like lumps (pi). This is likely to ventilate and regulate Liver pathogenic factors and reduce their solid accumulation. However, if there is stagnant Qi, it breaks the stagnation; if there is no stagnant Qi, it damages True Qi. Therefore, it must be selected and used with great caution. It is also stated that when Qingpi is charred black, it can enter the Blood aspect. Qingpi can also induce sweating; therefore, it should not be used in patients who already have spontaneous sweating.