禀天地纯阴之气以生，故其味苦涩，大寒，无毒。足厥阴、足少阴、足阳明三经药
也。铜刀切去芦，酒洗晒干，或用甘草汁浸一宿，晒干用。
龙胆草，止泻痢，去肠中小虫；却惊痫，益肝胆二气，胃中伏热，及时行温热。
能除下焦湿肿，并酒疸黄肿堪退；疗客忤肝气；治痈肿口疮；敌惊痫，杀蛊毒。酒浸为
柴胡辅佐，上行治眼目赤疼， 肉必加，翳障通用。空腹饵之，令尿不禁。
主治（痘疹合参） 专治痘疹，目赤肿痛，肝胆胃中实热，宜酒洗晒干用。虚人泻
泄并忌。
按∶龙胆草大苦大寒，譬之严冬暗淡惨肃，万卉凋残，先哲谓苦寒伐标，宜暂不宜
久。如盛世不废刑罚，所以佐得义之无穷。苟非气壮实热者，率而轻投，其败也必矣。
感天地苦寒之味，兼得春之升气以生者也。其味苦平，微寒，无毒。
茵陈蒿，专治黄胆。须分阴黄、阳黄。阳黄热多，有湿有燥，湿则佐以桅子、大
黄，燥则佐以栀子、橘皮；阴黄只属寒多，须附子其剂。总行滞气，解烦热，化痰利湿
之要药。入阳明、太阴，去湿除热，散结利水之神剂也。过用损伤元气。
主治（痘疹合参） 择陈久者佳，主去湿除热，散结利水，化痰行滞。凡夏月疮疹
热甚，小便不利者宜用。如痘子搔痒，可为熏药，亦以其能去湿热也。
龙胆草禀受天地纯阴之气而生，因此它的味道苦涩，性质大寒，无毒。它是入足厥阴肝经、足少阴肾经和足阳明胃经的药物。用铜刀切去芦头，酒洗后晒干，或者用甘草汁浸泡一夜，再晒干使用。
龙胆草能止住泻痢，去除肠道中的小虫；消除惊痫，补益肝胆二气，清除胃中潜伏的热邪，以及治疗时行温热病。它能清除下焦的湿肿，并退除因饮酒导致的黄疸肿胀；治疗客忤（外邪侵袭）引起的肝气问题；治疗痈肿和口疮；抵御惊痫，杀灭蛊毒。用酒浸泡后作为柴胡的辅佐药，可上行治疗眼睛红肿疼痛，在翳障（角膜云翳等眼疾）的治疗中通用。空腹服用会导致小便失禁。
主治（痘疹合参）：专门治疗痘疹，症状为眼睛红肿疼痛，肝胆胃中有实热，适宜用酒洗后晒干的方法炮制使用。体质虚弱者出现泄泻时应忌用。
按语：龙胆草味极苦性极寒，好比严冬时节阴暗肃杀，百花凋零。先哲认为苦寒之药容易损伤正气（伐标），适宜暂时使用而不宜长期服用。就像盛世也不废除刑罚，是为了辅助道义发挥无穷的作用。如果不是气壮且患有实热证的人，轻率地随意投药，必然会导致败坏身体。
茵陈蒿感受了天地苦寒的味道，又兼得春季升发之气而生。它的味道苦平，性质微寒，无毒。
茵陈蒿专门治疗黄疸。必须区分阴黄和阳黄。阳黄热邪较多，有湿也有燥，若有湿则佐以栀子、大黄；若偏燥则佐以栀子、橘皮；阴黄只属于寒邪较多，必须在方剂中加入附子。它是总行滞气、解除烦热、化痰利湿的重要药物。它入阳明经和太阴经，是去湿除热、散结利水的特效药剂。过量使用会损伤元气。
主治（痘疹合参）：选择陈久者为佳，主要功效是去湿除热、散结利水、化痰行滞。凡是夏季疮疹热势严重，小便不利者适宜使用。如果痘子瘙痒，可以将其作为熏蒸药物使用，也是因为它能去除湿热。
Longdancao (Radix Gentianae) is born by inheriting the pure Yin Qi of Heaven and Earth; therefore, its taste is bitter and astringent, its nature is greatly cold, and it is non-toxic. It is a herb entering the Foot Jueyin Liver Meridian, Foot Shaoyin Kidney Meridian, and Foot Yangming Stomach Meridian. Cut off the rhizome with a copper knife, wash with wine, and dry in the sun; or soak in Licorice Juice for one night, then dry in the sun for use.
Longdancao stops dysentery and diarrhea, removes small parasites from the intestines; expels fright and epilepsy, benefits the Qi of the Liver and Gallbladder, clears latent heat in the Stomach, and treats epidemic warm diseases. It can eliminate dampness and swelling in the Lower Jiao, and resolve jaundice and edema caused by alcohol consumption; treat Guest Wu (external pathogenic invasion affecting Liver Qi); treat carbuncles, sores, and mouth ulcers; resist fright and epilepsy, and kill Gu poison. When soaked in wine and used as an assistant to Chaihu (Bupleuri Radix), it ascends to treat redness and pain in the eyes, and is commonly used for nebula (corneal opacity). Taking it on an empty stomach may cause urinary incontinence.
Indications (Combined Reference on Smallpox and Rashes): Specifically treats smallpox and rashes characterized by red, swollen, and painful eyes, and excess heat in the Liver, Gallbladder, and Stomach. It should be prepared by washing with wine and drying in the sun. It is contraindicated for patients with deficiency constitutions suffering from diarrhea.
Commentary: Longdancao is extremely bitter and cold, resembling the dark and solemn atmosphere of severe winter when all flowers wither. Ancient sages stated that bitter-cold herbs attack the branch (symptoms) and are suitable for temporary use rather than long-term administration. Just as laws and punishments are not abolished even in prosperous times to assist righteousness indefinitely, so too must bitter-cold herbs be used judiciously. Unless the patient has strong Qi and excess heat, rashly administering this herb will inevitably damage the body.
Yinchenhao (Herba Artemisiae Scopariae) is born by sensing the bitter-cold flavor of Heaven and Earth, combined with the ascending Qi of Spring. Its taste is bitter and neutral, its nature is slightly cold, and it is non-toxic.
Yinchenhao specifically treats Jaundice (Huangdan). One must distinguish between Yin Jaundice and Yang Jaundice. In Yang Jaundice, heat is predominant, involving both dampness and dryness; if dampness prevails, assist with Zhizi (Fructus Gardeniae) and Dahuang (Radix et Rhizoma Rhei); if dryness prevails, assist with Zhizi and Juapi (Pericarpium Citri Reticulatae). Yin Jaundice belongs solely to excessive cold, requiring the addition of Fuzi (Radix Aconiti Lateralis Preparata) to the formula. It is a key herb for circulating stagnant Qi, relieving vexation and heat, transforming phlegm, and promoting urination to remove dampness. Entering the Yangming and Taiyin meridians, it is a miraculous agent for removing dampness, clearing heat, dissipating nodules, and promoting diuresis. Overuse damages Yuan Qi (Primary Qi).
Indications (Combined Reference on Smallpox and Rashes): Choose aged material for best results. Its main functions are removing dampness, clearing heat, dissipating nodules, promoting diuresis, transforming phlegm, and moving stagnation. It is suitable for summer cases where rashes are accompanied by intense heat and difficult urination. If pustules itch, it can be used as a fumigant, owing to its ability to clear damp-heat.