Polygala (yuan zhi)

What is polygala? What is it used for?

Polygala is a branching type of herb native to the central and western United States. There are several varieties of polygala, but the most common are P. senega, P. sibirica and P. tenuifolia. It earned its nickname of "Seneca snakewood" in the 1700s, when Seneca Indians used it to treat snakebites in American settlers.

The plant is a perennial herb, and can reach a height of 18 inches, with oval-shaped green leaves and pale red, yellow or lavender flowers, depending on the species. The plant’s root varies in color from yellowish-gray to brownish-gray, and is usually twisted or spiraled, with a thick, gnarled crown. The root is used medicinally.

As mentioned, polygala was traditionally used by native Americans to treat snakebites and as an expectorant to treat cough and bronchitis. In traditional Chinese medicine, other varieties of polygala are used for a variety of purposes, including the promotion of sleep and calming the spirit. Polygala is considered a powerful tonic herb that can help develop the mind and aid in creative thinking.

How much polygala should I take?

The standard dosage of polygala is 1.5-3 grams of dried root, 1.5-3 grams of a fluid extract or 2.5-7.5 grams of a tincture. A polygala tea can also be made, with a maximum of three cups per day.

What forms of polygala are available?

Fresh or dried polygala can be found at most herbal shops and Asian markets. Some stores also sell polygala extracts and tinctures.

What can happen if I take too much polygala? Are there any interactions I should be aware of? What precautions should I take?

Prolonged use of polygala may cause upset stomach and diarrhea; as such, it is contraindicated in patients who have ulcers or gastritis, and should not be used long-term. It also should not be used by women who are pregnant or lactating. As of this writing, there are no known drug interactions with polygala. As always, make sure to consult with a qualified health care provider before taking polygala or any other herbal remedy or dietary supplement.


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