History
Scutellaria baicalensis has been used in Chinese medicine for more than two thousand years. It was first mentioned in the ‘Shen Nong Ben Cao Jing’ / Divine Husbandman’s Classic of the Materia Medica from the Qin or Eastern Han dynasty (25 – 220CE). It was listed in the middle class of drugs ie. therapeutic substances with limited toxicity, intended to the treat the sick.
The formulas in the ‘Discussion of Cold-Induced Disorders’ (shang han lun), by Zhang Zhong-Jing, ( Han Dynasty, 220CE) included the formula Minor Bupleurum (xiao chai hu tang). This formula was traditionally used for harmonizing Lesser Yang syndrome (shao yang bing zheng) in acute febrile diseases caused by exogenous Cold (one of the six stages of disease progression described).
Scutellaria, along with Bupleurum, is the chief herb in this formula, clearing Heat from the Shao Yang level and descending Qi to reduce Qi obstruction.The formula is still in common use as an effective herbal formula for conditions such as post-viral recovery, food allergies and intolerances, digestive disorders and medicinal side effects.
From the Tang Dynasty (752), ‘Medical Essentials from the Imperial Library (wai tai mi yao) by Wang Tao was a comprehensive description of medical problems, including diabetes, It covered more than 1,000 categories, and over 6,000 herbal prescriptions, among which was the Heat and Toxin clearing ‘Coptis Decoction to Relieve Toxicity (huang lian jie du tang). Scutellaria is one of the four herbs in this very effective antimicrobial, anti-inflammatory and antipyretic formula that still has a central place in TCM clinics.
The broad acting ‘Gentiana Long Dan Decoction to Drain the Liver Formula’, (long dan xie gan tang) contains Scutellaria as a deputy herb, supporting Gentiana in reducing the heat in the Liver and Gall Bladder. This formula was first recorded in ‘Analytic Collection of Medical Formulas (yi fang ji jie) by Wang An in 1682.
It was first described, in Western terms, in a 1775 publication describing the flowering plants of the Baikal region in Russia by botanist Johann Gotlieb Georgi. It was later described by European botanists in China in the late 19th century.
Western herbalists are familiar with Scutellaria laterifolia common in the eastern states of North America where it is used as a mild nervine.
Botanical outline
Scutellaria baicalensis is in the family of frequently aromatic, flowering plants known as Lamiaceae, which includes the genera Salvia, Vitex, Thymus, Leonurus and Nepeta. It is one of over 200 species of the widespread genus Scutellaria, commonly known as Skullcaps.
It is a perennial herb, growing well in open areas and on sunny slopes, being drought tolerant and very hardy. It grows from .3m to 1.2m in height and has spear-shaped leaves. Its single stems bear a profusion of blue or purple flowers which have five petals fused into a tube that terminates in an upper lip and a lower lip.
The name Scutellaria is derived from the Latin ‘scultella’ which means ‘small dish’ and refers to the shape of the fruiting calyx. It takes the name ‘Skullcap’ from the caplike appearance of the outer whorl of its small flowers.
The root is the only part of Scutellaria baicalensis that is used. It is harvested at three to four years of age, both in spring and autumn. It is cleaned and sun dried till half dry, then the root bark is scraped off and the root dried or sliced and dried.
Medicinal properties
TCM: Listed under “Herbs that clear Heat”, in “Herbs that clear Heat and dry Dampness”, bitter, cold Scutellaria baicalensis (huang qin) enters the Lung, Stomach, Gall Bladder and Large intestine channels. It It clears Heat, especially in the Lung and Upper Burner (including acute and sub-acute skin disorders) and Dampness and Heat in the Gall Bladder and intestines. It is also used to clear Heat from accumulation in the Stomach and to stop vomiting, to clear toxins and stop bleeding. It is also used for abnormal foetal movements..
Scutellaria is contraindicated in cases of Cold from Spleen and Stomach deficiency. Being very cold and bitter, it can injure the Yang and the Spleen and Stomach Qi if taken for too long or in too big a dose.
General: The principal chemical compounds isolated from the root are the flavonoids baicalein, baicalin and wogonin.
It has anti-inflammatory, antioxidant, and anti-allergen actions and has exhibited hepatoprotective effects.
It has been shown to have diuretic, fever reducing and blood pressure lowering effects.An antihypertensive effect was demonstrated in an open study of 51 cases. ( Chang, H M et al: Advances in Chinese Medicinal Materials Research. World Scientific, Singapore (1985). )
One study found evidence that consumption of baicalin might lower blood levels of statin drugs. (The effect of herbal medicine baicalin on pharmacokinetics of rosuvastatin, substrate of organic anion-transporting polypeptide 1B1. Fan L, Zhang W, Guo D, et al. Clin Pharmacol Ther. 2007 Sep 12)
With the rise of antibiotic resistant infections such as MRSA and the increased potential for influenza pandemics, the search is on for new sources of treatment. The effectiveness of extracts such as baicalin from Scutellaria have gained increasing attention, both in isolation and in combination with antibiotics whose effectiveness has been compromised.
(Baicalin synergy with beta-lactam antibiotics against methicillin-resistant Staphylococcus aureus and other beta-lactam-resistant strains of S. aureus. Liu IX, Durham DG, Richards RM. J Pharm Pharmacol. 2000 Mar;52(3):361-6.)
An interesting paper from the Chonbuk National University, Jeonju, Korea concludes that Scutellaria baicalensis may have beneficial effects in the prevention or treatment of mast cell mediated allergic diseases.
(http://www.jops.co.kr/ojms_media/publications/2011/01-15/06 ScutellariaJH.164310.pdf Korean J Phys Anthropol Vol. 23, No. 4 (2010) pp. 217~227 )
Another species used in Chinese medicine is Scutellaria barbata or bearded skullcap, whose Chinese name is ban zhi lian / ”half branch lotus”. It is used for Heat Toxin swellings eg sores and abscesses.
Chinese Skullcap (Scutellaria baicalensis) is not interchangeable with American Skullcap (Scutellaria laterifolia). American Skullcap is known best as a herbal sedative used in treating premenstrual syndrome (PMS), insomnia, stress headaches, nervous tension, exhaustion, spasm and substance withdrawal. It was once called mad-dog weed because of its use during the eighteenth century to treat rabies. It is frequently used in homeopathic medicine. The medicinal parts of Scutellaria laterifolia are the leaves.