半夏

Pinellia tuber (Banxia)

Pharmaceutical Name: Rhizoma Pinelliae

Botanical Name: Pinellia ternata (Thunb.) Breit.

Common Name: Pinellia tuber

Source of Earliest Record: Shennong Bencao Jing

Part Used: The tuberous rhizomes are dug in the period between summer and autumn. After the bark and fibrous roots have been removed, the rhizomes are dried in the sun.

Natural Properties & Taste: Pungent, warm and toxic

Meridians: Spleen, stomach and lung

Therapeutic Effects:
1. To dry dampness and resolve phlegm.
2. To conduct rebellious qi downward and stop vomiting.

3. To reduce distension and disperse nodules.

Indications:
1. Phlegm-damp cough due to deficient spleen manifested as cough with profuse, dilute and white sputum. Pinellia tuber (Banxia) is used with Tangerine peel (Chenpi) and Poria (Fuling) in the formula Erchen Tang.

2. Nausea and vomiting due to rebellious stomach qi: a) stomach cold typePinellia tuber (Banxia) is used with Fresh ginger (Shengjiang) in the formula Xiao Banxia Tang. b) stomach heat typePinellia tuber (Banxia) is used with Bamboo shavings (Zhuru) and Loquat leaf (Pipaye). c) pregnancy typePinellia tuber (Banxia) is used with Perilla stem (Sugeng) and Amomum fruit (Sharen). d) stomach weakness typePinellia tuber (Banxia) is used with Ginseng (Renshen) and Jujube (Dazao).

3. Globus hystericus due to qi stagnation and accumulation of phlegm-damp manifested as a feeling of having a foreign body in the throat, fullness and distension in the chest and epigastric region and nausea. Pinellia tuber (Banxia) is used with Magnolia bark (Houpo), Perilla leaf (Zisuye) and Poria (Fuling) in the formula Banxia Houpo Tang.

4. Goiter, scrofula and subcutaneous nodule. Pinellia tuber (Banxia) is used with Laminaria (Kunbu), Seaweed (Haizao) and Tendrilled fritillary bulb (Chuanbeimu).

Dosage: 5-10 g

Cautions & Contraindications: This herb is contraindicated in cases with dry cough due to deficient yin, or cough due to phlegm-heat. Also, it cannot be used together with the herb Sichuan aconite root (Wutou).