Skip to content

Zi Cao

Lithospermum erythrorhizon Sieb. et Zucc.; Arnebia euchroma (Royle) Johnst.

Genus: Lithospermum Species: erythrorhizon Pinyin: Zi Cao Latin: Radix Arnebiae seu Lithospermi
Gromwell root (English) ็ดซ่‰ (Chinese)

โ˜ฏ TCM Properties

Category: clearing_heat
Temperature: cold
Taste: sweet, salty
Meridians: heart, liver
Functions:

Cools the Blood; Resolves Toxicity; Vents Rashes; Invigorates Blood and Dispels Stasis; Moistens the Intestines and Unblocks the Bowels

Botanical Description

Lithospermum erythrorhizon is a perennial herb of the family Boraginaceae native to grassy hillsides and open woodland in China, Korea and Japan. From a thick, woody, deeply purple-red taproot it produces several erect, bristly-hairy stems 40-90 cm tall bearing alternate, sessile, lanceolate to ovate-lanceolate leaves 3-8 cm long with strigose hairs on both surfaces. Small white, salverform flowers about 5-6 mm across with five spreading corolla lobes and a tubular throat are borne in terminal scorpioid cymes from June to August, followed by smooth, shining grey-white ovoid nutlets. The medicinally used root, harvested in autumn, is cylindrical, twisted, 7-14 cm long and 1-2 cm thick, with deeply furrowed purple-red bark that stains the fingers due to its high content of naphthoquinone pigments (shikonin and acetylshikonin).

Dosage

Form Amount Frequency Duration Population Notes
decoction 6-15g Daily โ€” โ€” โ€”

Cultural & Historical Context

Traditional Chinese Uses

Zi Cao (gromwell root) is a cold herb that cools the Blood and clears Heat toxin, with particular utility in treating conditions where Heat has entered the Blood level. It is a key herb for measles and rashes that are slow to erupt or appear purplish โ€” indicating trapped heat in the blood. Topically it is used for burns, skin ulcers, and inflammatory skin conditions. Modern preparations for wounds and eczema continue its traditional external application.

Traditional American Uses

None Documented

Important Disclaimer

This information is for educational purposes only and is not intended to replace professional medical advice. Always consult a qualified healthcare provider before using any herbal remedy, especially if you are pregnant, nursing, or taking medications.