In Traditional Chinese Medicine, herb-to-herb interactions have been known for a long time, and include both synergistic as well as antagonistic interactions.
Synergistic Interactions are of the following two types:
- Mutual Accentuation (Xiang Xu) - 相须
- Mutual Enhancement (Xiang Shi) - 相使
In Mutual Accentuation, two herbs with similar functions are used together to increase their therapeutic effect. Examples include:
- Jing Jie (荆芥) with Fang Feng (防风) to expel wind and release the exterior
- Jin Yin Hua (金银花) with Lian Qiao (连翘) to reduce heat-toxin
- Da Huang (大黄) with Mang Xiao (芒硝) to promote bowel movement
In Mutual Enhancement, two herbs with different functions are used. The first directly targets the pathological condition, and the second increases the therapeutic effect of the first. Examples include:
- Zhi Mu (知母) with Huang Bai (黄柏), where Zhi Mu nourishes yin of the kidney and clears heat in the Lower-Jiao, while Huang Bai reduces empty-heat in the Lower-Jiao and is able to enhance the function of Zhi Mu.
- Fu Zi (附子) with Zhi Gan Cao (炙甘草), where sweet Gan Cao can moderate the speed of hot Fu Zi.
- Da Huang (大黄) with Zhi Gan Cao (炙甘草), where sweet Gan Cao can reduce the harsh purging effect of Da Huang.
Antagonistic Interactions are of the following four types:
- Mutual Counteraction (Xiang Wei) - 相畏
- Mutual Suppression (Xiang Sha) - 相杀
- Mutual Antagonism (Xiang Wu) - 相恶
- Mutual Incompatibility (Xiang Fan) - 相反
In Mutual Counteraction, the characteristic side effects or toxicity of the first herb can be minimized or neutralized by the second herb. An example is:
- Ban Xia (半夏) with Sheng Jiang (生姜), where the toxic effects of Ban Xia can be reduced by Sheng Jiang.
In Mutual Suppression, the first herb suppresses or minimizes the toxicity of the second herb. Examples include:
- Lv Dou (绿豆) with Ba Dou (巴豆), where Lv Dou can reduce the toxicity of Ba Dou.
- Ge Hua (葛花) with alcohol (酒), where Ge Hua can reduce the toxicity of ethanol.
The following is the classic list of eighteen substances that exhibit Mutual Antagonism to each other. For example, the effects of Ding Xiang will be countered by Yu Jin, and the herbs should not be taken together, although both are very common herbs.
|No.||Herb Name||Counteracting Herb Name|
|1||Mercury (Shui Yin) 水银||Arsenolite (Pi Shuang) 砒霜|
|2||Rhizoma Euphorbiae E. (Lang Du) 狼毒||Lithargyrum (Mi Tuo Seng) 密陀僧|
|3||Semen Crotonis (Ba Dou) 巴豆||Semen Pharbitidis (Qian Niu Zi) 牵牛子|
|4||Flos Caryphyili (Ding Xiang) 丁香||Radix Curcumae (Yu Jin) 郁金|
|5||Nitrum Depuratum (Ya Xiao) 牙硝||Rhizoma Sparganii (San Leng) 三棱|
|6||Cornu Rhinoceri (Xi Jiao) 犀角||Rhizoma Aconiti Kusnezoffii (Cao Wu) 草乌|
|7||Cornu Rhinoceri (Xi Jiao) 犀角||Rhizoma Aconiti (Chuan Wu) 川乌|
|8||Radix Ginseng (Ren Shen) 人参||Rhizoma Trogopterorum (Wu Ling Zhi) 五灵脂|
|9||Cortex Cinnamomi (Rou Gui) 肉桂||Hallositum Rubrum (Chi Shi Zhi) 赤石脂|
|10||Sulfur (Liu Huang) 硫磺||Mirabilitum (Mang Xiao) 芒硝|
The following is the classic list of nineteen substances that are incompatible with each other, and using them together can have dangerous results:
- Gan Cao (甘草) is incompatible with the following:
- All forms of Wu Tou (乌头), including Chuan Wu (川乌), Cao Wu (草乌) and Fu Zi (附子), are incompatible with the following:
|1||Chuan Bei Mu||川贝母|
|2||Zhe Bei Mu||浙贝母|
|3||Gua Lou, Gua Lou Ren, Gua Lou Pi||栝楼, 栝蒌仁, 栝蒌皮|
|7||Tian Hua Fen||天花粉|
- Li Lu (藜芦) is incompatible with the following:
|2||Bei Sha Shen||北沙参|
|3||Nan Sha Shen||南沙参|
Although rather rare, some herbs may be used alone (单行) because they have reasonably balanced properties and functions. These include
- Ren Shen
- Dan Shen
- Dang Gui
- Gan Cao
Herbs That Are Prohibited During Pregnancy
|10||Jing Da Ji||京大戟|
|17||Qian Niu Zi||牵牛子|
|21||Ma Qian Zi||马钱子|
Herbs That Are Used With Caution During Pregnancy
|6||Mu Dan Pi||牡丹皮|
|12||Fan Xie Ye||番泻叶|