Mao Gen
StarRanunculus japonicus Thunb.
Synonyms: Ranunculus japonicus Thunb., Ranunculus acris subsp. japonicus (Thunb.) Hultén
☯ TCM Properties
Absorbs pus
Traditional Chinese Uses
Mao Gen, more fully Bai Mao Gen (Rhizoma Imperatae), is the white creeping rhizome of Imperata cylindrica (cogon grass). It is sweet in flavour and cold in nature, entering the Lung, Stomach and Bladder channels. Placed among the herbs that cool the Blood to stop bleeding, it cools Blood-level Heat to arrest bleeding, clears Heat from the Lung and Stomach to relieve thirst and irritable heat, and promotes urination to drain Damp-Heat.
It is used for warm-febrile disease with thirst, and especially for Heat-type bleeding such as epistaxis, haemoptysis and haematuria, where it guides Heat out through the urine. It also treats oedema, painful or scanty urination, and Damp-Heat jaundice. Being cold and sweet, its pleasant decoction is often taken alone or with herbs such as Xiao Ji or Ou Jie; it should be used cautiously in Spleen-deficiency cold patterns.
Western Herbalism Properties
Botanical Description
Mao Gen is the whole herb and root of Ranunculus japonicus Thunb. (Ranunculaceae), the East Asian buttercup — a perennial herb 30–70 cm tall with fibrous roots, erect branching stems, and long-stalked, palmately 3–5-parted basal leaves with toothed lobes. Bright glossy yellow, five-petalled flowers are borne on slender branches in spring and summer, followed by clustered flattened achenes. The fresh plant contains ranunculin, which on crushing releases the potent vesicant protoanemonin. It is a toxic, acrid, warm drug used almost entirely externally — the mashed fresh herb is applied to acupoints or lesions to raise a counter-irritant blister for malaria, jaundice, rheumatic pain, and swellings. Not to be confused with Bai Mao Gen (Imperata cylindrica), an unrelated sweet, cold blood-cooling grass.
Damp meadows, stream banks, ditch margins, and grassy slopes across lowland and montane East Asia.
Dosage
| Form | Amount | Frequency | Duration | Population | Notes |
|---|---|---|---|---|---|
| decoction | 6-15g | Daily | — | — | — |
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.
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