What it is:
This herb is thebulb of Allium macro-stemon Bge. (family Liliaceae) which grows in all parts of China. It is collected insummer and autumn,washed clean afterremoval of the stemsand leaves steamed or scalded and dried insunlight for use.

Property:
Pungent and bitter in flavour, warm in pro-perty, acting on the lung, stomach and large intestine channels.

Effects:
Relieving the obstruction of yang-qi to disperseaccumulation of path-ogen and promotingcirculation of qi to remove stagnation.

Used for:
1. For obstruction of qi in the chest andchest pain due to accumulation of cold phlegm and obstruction of yang in the chest, it is always used with trichosanthes fruit,as in Decoction ofTrichosanthes andAllium with Wine(Gualou Xiebai Baijiu Tang) and Decoction ofTrichosanthes, Allium and Pinellia (Gualou Xiebai Banxia Tang) . In cases of simul-taneous existence of severe stagnation of qi and accumulation of phlegm manifestedas oppressed feeling in the chest, short breath, and cough with profuse sputum, the above herbs should bedispensed with imma-ture bitter orange and magnolia, as in Decoction of Immature Bitter Orange, Macos-tem Onion and Cinna-mon Twig (Zhishi Xiebai Guizhi Tang). In cases of simul-taneous existence of blood stasis withmanifestations ofstabbing pain in the chest and back,red sage root, saf-flower and red peonyroot should be added to the above recipes.

2. Diarrhea anddysentery with ten-esmus due to stagna-tion of qi in the stomach and intes-tines. It can be used with bupleurum root, white peony root and immature bitterorange. In cases ofdiarrhea and dysen-tery with tenesmus due to damp- heat in the stomach andintestines, macrostem onion should be used in combination with phellodendron barkand ash bark.

Dosage andadministration: 5-10g, decocted in water for an oral dose.

Precautions:
This herb should not begiven to those who have insufficiency of qi but without stag-nation, poor appetite due to weak stomach, or who cannot endurethe odour of garlic. Choice recipes: 1. Chest pain due to obstruction of qi: One trichosantheskernel (pounded),macrostem onion 15gand pinellia tuber 15g, decocted in water and a little wine and taken in three doses. 2. Dysentery:macrostem onion 9g and phellodendron bark 9g, decocted in water for an oral dose.