Herbs & Botanicals
Corydalis (yan hu suo)
What is corydalis? What is it used for?
Corydalis is a tall, thin herb native to the Zhejiang province of China.
The plant consists of a thin, green stem with green leaves and yellow
flowers. The rhizome is used for medicinal purposes.
In traditional Chinese medicine, corydalis is believed to invigorate
the blood, facilitate the movement of qi throughout the body, and reduces
menstrual, abdominal and hernial pain.
To date, a total of 20 alkaloids have been isolated in corydalis, the
most powerful of which is a compound called tetrahydropalmatine (THP).
Lab tests have shown that THP acts as an analgesic and sedative and can
have a wide range of actions on the central nervous system. Animal studies
have found that THP decreases the stickiness of platelets, which helps
protect against heart attacks and strokes, and can lower heart rate and
blood pressure. Human trials have found that THP can help people with
insomnia fall asleep easier, without any adverse side effects, and a Chinese
study conducted in 1990 found that HTP could reduce nerve pain and pain
associated with menstruation.
How much corydalis should I take?
The recommended dosage for corydalis is 5-10 grams per day of the dried
rhizome. Some practitioners recommend an alternative of 10-20 millileters
of an extract daily as an alternative.
What forms of corydalis are available?
Many Asian markets and specialty stores sell dried or powdered corydalis
root. Corydalis is also available as a tablet or as an alcohol-based extract.
What can happen if I take too much corydalis?
Are there any interactions I should be aware of? What precautions should
The American Herbal Products Association has assigned corydalis a class
2B rating, meaning that it should not be taken by pregnant or nursing
women. Some individuals who take large doses of corydalis may experience
vertigo, fatigue or nausea. In addition, there have been many reports
of subjects experiencing THP toxicity, which could lead to hepatitis.
At present, there are no known drug interactions with corydalis.
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