Macrostem onion (Xiebai)
Allium macrostemon Bge. (Fam. Liliaceae)
Pharmaceutical Name: Bulbus Allii macrostemi
Botanical Name: Allium macrostemon Bge. (Fam. Liliaceae)
Common Name: Macrostem onion, Bakeri, Bulb of Chinese chive, Long stamen onion bulb.
Source of Earliest Record: Shennong Bencao Jing
Part Used & Method for Pharmaceutical Preparations: The macrostem, or bulb, of the onion is dug in May, cleaned and dried in the sun.
Properties & Taste: Pungent, bitter and warm
Meridians: Lung, stomach and large intestine
Functions: 1. To promote the flow of yang and dissipate cold phlegm; 2. To regulate qi and reduce stagnation.
Indications & Combinations:
1. Cold phlegm stagnated in the chest manifested as stifling sensation and pain in the chest and dyspnea. Macrostem onion (Xiebai) is used with Trichosanthes fruit (Gualou) in the formula Gualou Xiebai Baijiu Tang.
2. Dysentery manifested as tenesmus. Macrostem onion (Xiebai) is used with Immature bitter orange (Zhishi), Costus root (Muxiang) and White peony root (Baishao).
3. For Stagnant Qi in Stomach and Intestine with diarrhea and dysentery with tenesmus, it is used with Radix Bupleuri (Chai Hu), Radix Paeoniae Alba (Bai Shao), and Fructus Aurantii Immaturus (Zhi Shi), or with Cortex Phellodendri (Huang Bai) and Cortex Fraxini (Qin Pi).
Dosage: 5-10 g, decocted in water for an oral dose.
Cautions & Contraindications:
1. Contraindicated in patients with Deficient Qi.
