气温，味苦、甘，纯阳。
《象》云∶主诸风湿冷，通五脏，去腹内瘕滞，腰膝冷痛，及治伤损。铁脚者佳。去芦
用。
《心》云∶去大肠之风。
《本草》云∶忌茗。
气温，味大辛，纯阳。性温，气浓于味，阳也。无毒。
少阴经药，手少阴引经之药。
《象》云∶治少阴头痛如神，当少用之。独活为使，为主用。去头芦并叶。华州者佳。
《珍》云∶主少阴经头痛。
《心》云∶主诸项头痛，诸风通用之。味辛热，温阴经，散水寒以去内寒。
《本草》云∶主咳逆头痛脑动，百节拘挛，风湿痹痛，死肌，温中下气，破痰，利水道
，开胸中，除喉痹， 鼻，风痫癫疾，下乳结，汗不出，血不行，安五脏，益肝胆，通精气
。久服明目，利九窍。
东垣云∶治邪在里之表，故仲景少阴证，用麻黄附子细辛汤也。
易老云∶治少阴头痛。太阳则羌活，少阴则细辛，阳明则白芷，厥阴则川芎、吴茱萸，
少阳则柴胡。用者随经不可差。细辛香味俱缓，故入少阴，与独活颇相类。
《本草》又云∶曾青、枣根为之使，得当归、芍药、白芷、川芎、牡丹、 本、甘草，
共疗妇人。得决明、鲤鱼胆汁、青羊肝，共疗目痛。恶野狼毒、山茱萸、黄 ，畏硝石、滑石
，反藜芦。
《衍义》云∶治头面风痛，不可缺也。
(Weilingxian) The thermal nature is warm, the flavors are bitter and sweet, belonging to pure Yang.
*Yi Xiang* states: It governs various wind-damp-cold pathogens, unblocks the five zang organs, eliminates abdominal masses and stagnation, treats cold pain in the waist and knees, and manages traumatic injuries. Those with iron-like roots are superior. Use after removing the rhizome (lu).
*Yao Xing Xin Wu* states: Expels wind from the Large Intestine channel.
*Ben Cao* states: Avoid using with tea.
(Xixin) The thermal nature is acrid, belonging to pure Yang. The nature is warm; its qi aspect is stronger than its flavor aspect, thus it is Yang. Non-toxic.
It is a herb of the Shaoyin channel and a guiding herb for the Hand-Shaoyin channel.
*Yi Xiang* states: It treats Shaoyin headache with miraculous effect; it should be used in small doses. When Du Huo is used as an assistant, Xixin serves as the principal herb. Use after removing the head, rhizome, and leaves. Those from Huazhou are superior.
*Yao Zhen* states: It governs Shaoyin channel headaches.
*Yao Xing Xin Wu* states: It governs various neck/headaches and is generally applicable to all wind conditions. With an acrid-hot flavor, it warms the Yin channels, disperses water-cold to remove internal cold.
*Ben Cao* states: It governs cough with rebellious qi, headache with brain movement, spasms and contractures in all joints, wind-damp bi pain, dead flesh, warms the middle and directs qi downward, breaks phlegm, promotes urination, opens the chest, eliminates throat obstruction, nasal congestion, wind epilepsy and mania, resolves breast milk accumulation, induces sweating when absent, promotes blood circulation, calms the five zang organs, benefits the liver and gallbladder, and unifies essence and qi. Long-term use brightens the eyes and benefits the nine orifices.
Li Dongyuan says: It treats exterior syndromes where the pathogen is interior; therefore, Zhang Zhongjing uses Mahuang Fuzi Xixin Tang for Shaoyin syndromes.
Zhang Yuansu (Yi Lao) says: It treats Shaoyin headaches. For Taiyang channel headaches, use Qiang Huo; for Shaoyin channel headaches, use Xixin; for Yangming channel headaches, use Baizhi; for Jueyin channel headaches, use Chuanxiong and Wuzhuyu; for Shaoyang channel headaches, use Chaihu. Practitioners must select herbs according to the channel without error. Xixin has mild aroma and flavor, thus entering the Shaoyin channel; it is quite similar to Du Huo.
*Ben Cao* further states: Ceng Qing and Zaogen serve as its assistants; combined with Dang Gui, Shaoyao, Baizhi, Chuanxiong, Mudan Pi, Gaoben, and Gancao, it jointly treats women's diseases; combined with Juemingzi, carp bile, and Qingyanggan, it jointly treats eye pain. It is incompatible with Yelangdu, Shanzhuyu, and Huangqin; it fears Xiaoshi and Huashi; and it is antagonistic to Lilü.
*Yanyi* states: It treats wind-pain of the head and face and is indispensable.