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Bi Ma Zi

Ricinus communis L.

Genus: Ricinus Species: communis Pinyin: Bi Ma Zi Latin: Semen Ricini
Castor bean seed (English) 蓖麻子 (Chinese)

☯ TCM Properties

Category: external_applications
Temperature: neutral
Taste: sweet, pungent
Meridians: large_intestine, lung
Functions:

Reduces Swelling and Draws Out Toxins; Purges Heat and Unblocks the Bowels; Unblocks the Channels and Collaterals

Western Herbalism Properties

Actions:
analgesicvulnerary

Botanical Description

Ricinus communis, the castor bean, is a fast-growing woody perennial shrub in the family Euphorbiaceae, native to northeastern Africa and now naturalized pantropically; in temperate climates it behaves as a tall annual. It can reach 2-6 meters, with smooth, hollow, reddish to greenish stems and very large, alternate, palmately lobed leaves up to 60 cm across with 5-11 serrated lobes and long, reddish petioles. Monoecious inflorescences are terminal panicles bearing greenish staminate flowers below and spiny reddish pistillate flowers above. The fruit is a spiny three-chambered capsule, 1.5-2.5 cm, that splits explosively to release three glossy, mottled, ovoid seeds resembling engorged ticks. The seeds contain the highly toxic protein ricin.

Dosage

Form Amount Frequency Duration Population Notes
poultice As needed Daily

Cultural & Historical Context

Traditional Chinese Uses

Bi Ma Zi (castor bean seed) is a sweet-pungent, neutral herb used in Chinese medicine both internally and externally with quite different applications. Externally, the fresh crushed seed or oil draws out and disperses swellings, abscesses, and carbuncles, and is used for prolapse of organs including rectal and uterine prolapse when applied to specific acupressure points. Internally, castor oil powerfully lubricates and purges the intestines. Due to the toxicity of ricin in the raw seed, castor bean must be carefully prepared and professionally administered.

Traditional American Uses

Castor seed and seed oil were used by multiple North American Indigenous groups primarily as topical dermatological aid and analgesic. Pima applied seed oil externally for skin conditions; Cherokee and Cahuilla used preparations as analgesics; Navajo, Seminole, and Diegueno recorded additional dermatological, contraceptive, and pediatric applications. Many uses were strictly external due to the seed's extreme toxicity (Moerman, 1998).

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.