生平泽。三四月茎端作穗。长一二寸。穗中开淡紫花。结子亦作穗。五月便枯。宜四月
收采。寇氏误为茺蔚。不知茺蔚有臭味。而夏枯绝无。且夏枯先枯而无子。茺蔚后枯而有子。
明是两物。（丹溪）
茎叶
味苦辛气寒。入足厥阴少阳经。土瓜（即王瓜）为之使。主治寒热瘰 鼠 。破症散瘿
结气。疗头疮喉肿。脚肿湿痹。补肝明目。有补养厥阴血脉之功。其退寒热。惟虚者可使。
（丹溪）治目珠疼至夜则甚者极效。或用苦寒药点之反甚者尤效。夫夜与寒皆阴。此草禀纯
阳之气而遇阴以化。补养厥阴血脉。故如神取效也。（全善）冬至生。夏至枯。具三阳之正
体。寒水之正化。故从内达外。自下彻上。以去寒热气结。及合湿成痹也。得连翘贝母元参
薄荷忍冬藤栝蒌根紫背天葵蓖麻仁甘草。治一切瘰 有效。得蒲公英。治一切乳痈乳岩。单
取数两。水煮浓汁。入生甘菊紫地丁忍冬藤连翘白芨白蔹甘草生地白芷半枝莲。消一切痈疽
肿毒。止痛有神。肝虚目睛疼。冷泪不止。血脉痛。羞明怕日。夏枯草五钱。香附一两为末。
每服一钱。茶调下。时疫喉肿盛行。捣烂渍水。去渣。少加酒服。已病者速愈。未病者不染
。诚退肿要药也。血崩不止。夏枯草为末。每服方寸匕。米饮调下。产后血晕。心气欲绝者
。夏枯草捣绞汁。服一大盏妙。瘰 马刀。不问溃与未溃。或日久。或成漏。用夏枯草六两
。水二钟。煎七分。食远温服。虚甚者。煎汁熬膏服。并涂患处。兼以十全汤加香附贝母远
志尤善。此味生血。乃治瘰 之圣药也。
〔论〕夏枯草以冬至后发生。夏至后枯瘁。其气寒。其味苦辛。谓为阳是也。谓为纯阳
则犹未尽也。卢子由云。具三阳之正体。寒水之正化。庶几近之而未晰其微也。盖阳在下。
由阴而生。在上即由阴而化。阴在上。由阳而生。在下即由阳而化。夏枯草本于阴。遇阳之
生以生。迨饱历阳气。以至阳极遇阴生遂枯者。非恶阴也。阳极将尽。径趋阴以化也。如人
身所病。阳盛而不得阴以化。则气结。而血亦结。此味于瘰 鼠 。症 结气。破之有专功。
可以思其微矣。夫阳遇阴化。则目珠痛之治。如他苦寒品味独非阴乎。何以点之反甚。而夏
枯草何以独别。盖此味一物。具有阴遇阳生。阳遇阴化之妙。更妙于阳气趋阴以化。气得化
而即能化血。不等于以阴制阳者。反不能化血也。治失血后不寐。经言卫气不得入于阴。宜
用半夏汤。以半夏得一阴之气而枯。犹是生于阳成于阴者。但其性燥。不宜于血证。代以夏
枯草饮之。其卧立至。绎此岂非阳得阴以化。故阳入阴中而俾卧至乎。又兹物遇阴而枯。枯
者告成之会。故曰成于阴。讵知阳之化于阴也。正以成其阳。有阴以成其阳。而阳之用不穷。
故楼氏谓目珠痛之治。不以阴而以阳也。阳得化于阴。则气化而后血化。诸方用以补肝明目
。并治血晕血崩。须识此义。
〔修治〕 用叶茎。其味苦辛。苦胜于辛。但茎之苦辛不及叶。似宜多用叶。
Grows in marshy and swampy areas. In the third and fourth lunar months, spike-like inflorescences emerge at the tips of the stems, measuring one to two cun in length. Pale purple flowers bloom within the spikes, and the seeds also form in spike clusters. The plant withers in the fifth month. It is suitable for harvesting in the fourth month. Kou Zongshi mistakenly identified it as *Leonurus japonicus* (Yimucao), not knowing that *L. japonicus* has an odor, whereas *Prunella vulgaris* (Xiakucao) has absolutely no scent. Moreover, *P. vulgaris* withers before producing seeds, while *L. japonicus* produces seeds after withering. These are clearly two different substances. (Zhu Zhenheng)
Stems and Leaves
Taste: bitter, pungent. Nature: cold. Meridian tropism: Foot Jueyin Liver meridian and Foot Shaoyang Gallbladder meridian. *Trichosanthes cucumerina* (Tuigua, i.e., *Trichosanthes kirilowii* var. *thunbergiana*) serves as a guiding herb. Indications: alternating chills and fever, scrofula (lymph node tuberculosis), rat fistula (chronic suppurative disease of the neck and axilla). It breaks up masses, dissipates goiter and qi stagnation. Treats head sores, throat swelling, foot edema, and damp bi syndrome. It nourishes the liver and improves vision, possessing the function of nourishing the blood vessels of the Jueyin. Its ability to resolve chills and fever is applicable only to deficiency patterns. (Zhu Zhenheng) For eye pain that worsens at night, it is extremely effective; if treatment with bitter-cold herbs applied topically causes worsening, using this herb is particularly effective. Night and cold both belong to Yin. This herb embodies pure Yang Qi and transforms upon encountering Yin, thereby nourishing the Jueyin blood vessels, which explains its miraculous speed. (Quan Shan) It grows at the Winter Solstice and withers at the Summer Solstice, embodying the correct structure of the Three Yang and the correct transformation of Cold Water. Thus, it acts from the interior to the exterior, from below to above, resolving cold-heat qi stagnation and bi syndrome formed by dampness. Combined with *Forsythia suspensa* (Lianqiao), *Fritillaria cirrhosa* (Beimu), *Scrophularia ningpoensis* (Xuanshen), *Mentha haplocalyx* (Bohe), *Lonicera japonica* (Rendongteng), *Trichosanthes kirilowii* root (Gualougen), *Panax notoginseng* leaf? No, *Basella alba*? No, *Zi Bei Tian Kui*, *Ricinus communis* seed (Bimaren), and *Glycyrrhiza uralensis* (Gancao), it effectively treats all types of scrofula. Combined with *Taraxacum mongolicum* (Pugongying), it treats all types of mastitis (Ru Yong) and breast cancer (Ru Yan). Using several liang alone, boiled in water to make a concentrated decoction, added with fresh *Chrysanthemum indicum* (Ganju), *Viola yedoensis* (Zi Di Ding), *Lonicera japonica* (Rendongteng), *Forsythia suspensa* (Lianqiao), *Bletilla striata* (Baiji), *Ampelopsis japonica* (Bailian), *Glycyrrhiza uralensis* (Gancao), *Rehmannia glutinosa* (Shengdi), *Angelica dahurica* (Baizhi), and *Scutellaria barbata* (Ban Zhilian), it eliminates all carbuncles, ulcers, swellings, and toxins, providing divine pain relief. For liver deficiency causing eye pain, incessant cold tears, vessel pain, photophobia, and fear of sunlight, use five qian of *Prunella vulgaris* (Xiakucao) and one liang of *Cyperus rotundus* (Xiangfu), ground into powder. Take one qian per dose, mixed with tea. During epidemics of throat swelling, crush the herb, soak in water, strain, add a little wine, and drink. Those already ill will recover quickly; those uninfected will remain so. It is indeed a key herb for reducing swelling. For metrorrhagia that does not stop, grind *Prunella vulgaris* (Xiakucao) into powder. Take one fangcunbi per dose, mixed with rice water. For postpartum syncope with impending loss of Heart Qi, crush *Prunella vulgaris* (Xiakucao), extract the juice, and drink one large cup; this is excellent. For scrofula and mar刀的 (axillary masses), whether ulcerated or not, chronic or forming sinuses, use six liang of *Prunella vulgaris* (Xiakucao) and two zhong of water, decoct to seven parts. Take warm after meals. For severe deficiency, decoct into a paste for oral administration and topical application. Concurrently administering *Shiquan Dabu Decoction* (Shiquan Tang) augmented with *Cyperus rotundus* (Xiangfu), *Fritillaria cirrhosa* (Beimu), and *Polygala tenuifolia* (Yuanzhi) yields even better results. This herb generates blood and is the sacred medicine for treating scrofula.
[Discussion] *Prunella vulgaris* (Xiakucao) emerges after the Winter Solstice and withers after the Summer Solstice. Its nature is cold, and its taste is bitter and pungent. To say it is Yang is correct. To say it is purely Yang is incomplete. Lu Ziyu stated: "It possesses the correct structure of the Three Yang and the correct transformation of Cold Water." This is close but does not fully clarify the subtleties. Generally, Yang Qi arises from Yin when located below, and transforms via Yin when located above. Yin Qi arises from Yang when located above, and transforms via Yang when located below. *P. vulgaris* originates from Yin, growing when Yang Qi begins to generate. When it has fully experienced Yang Qi until the extreme of Yang encounters Yin to generate withering, it is not due to aversion to Yin, but because the extreme of Yang is nearing its end and directly tends toward transformation into Yin. In human pathology, when Yang is excessive and cannot be transformed by Yin, Qi stagnates, and Blood also stagnates. This herb has specific efficacy in breaking up scrofula, rat fistula, masses, and qi stagnation, allowing us to ponder its subtleties. When Yang encounters Yin, it transforms. Therefore, regarding the treatment of eye pain, do other bitter-cold herbs not belong to Yin? Why does applying them worsen the condition, while *P. vulgaris* works differently? Essentially, this single herb contains the wonder of Yin generating Yang and Yang transforming via Yin. More wondrously, as Yang Qi tends toward Yin for transformation, Qi transforms and subsequently generates Blood, unlike methods that merely suppress Yang with Yin, which fail to generate Blood. For insomnia following blood loss, the classics state that when Wei Qi cannot enter Yin, *Banxia Decoction* should be used. *Pinellia ternata* (Banxia) acquires Yin Qi and withers, still being born in Yang and completed in Yin. However, its nature is dry and unsuitable for blood disorders. Replacing it with *Prunella vulgaris* (Xiakucao) decoction induces immediate sleep. Analyzing this, is it not because Yang, transformed by Yin, enters Yin, thus inducing sleep? Furthermore, this herb withers upon encountering Yin; withering signifies completion, hence "completed in Yin." Does this not mean that Yang transforms in Yin precisely to complete its Yang? With Yin completing Yang, the function of Yang becomes inexhaustible. Thus, Lou Shi stated that treating eye pain relies on Yang rather than Yin. When Yang is transformed by Yin, Qi transforms and then Blood transforms. Various formulas use it to nourish the liver and improve vision, and to treat syncope and metrorrhagia. One must understand this principle.
[Preparation] Use the leaves and stems. The taste is bitter and pungent, with bitterness predominating over pungency. The bitterness and pungency of the stems are inferior to those of the leaves; therefore, it seems advisable to use more leaves.