property and effect of Chinese Medical herbs(2)---------five flavours

The Chinese Medicine are not only classified into four characters, but also into five types to their flavours, such as acridness, sweetness, sourness, bitterness and saltiness. Some herbs possess no distinct flavour and are said to be "bland", but actually the taste slightly sweet. So it is accustomed to group the sweet drugs with the bland ones together, and classify as a "sweet-bland" flavour.

The actions of the five flavours can be summarised as follows:

acrid flavour can expel and activate;
sour flavour can astringe and preserve;
sweet flavour can tonify, regulate and moderate;
bitter flavour can dry , lower and release;
salty flavour can soften and purge;
bland flavour can promote diuresis.


The five flavours can be directly differentiated by the taste organ, but may also be determined by the effects of clinical practice. For instance, Radix Pureariae(Ge Gen) is proved clinically to be an agent for expelling superficial evils and acrid flavour has the same action, so it is considered that Radix Pureariae(Ge Gen)
has an acrid flavour. But in fact, it is not true. It is evident that such inference is not always accurate, since the action of herbs is not entirely determined by their flavours. Hence, those recorded in the literature may not be coincident with the actual flavour of the drugs.

property and effect of traditional Chinese Medical herbs(1)------------Four Characters

The four characters denote an over-all property of the Chinese medicines, i.e., cold, hot, warm and cool. In general, cold and cool as well as hot and warm are of the similar property but of various degrees. That is to say , a cool drug is slightly  cold while a hot one is extremely warm. In addition, there are some medicines which are neither cool nor warm and are said to be " neutral". In fact, although the character of " neutral" drugs is not so evident, yet they trend to be sightly cool or slightly warm. So they are not classified as a special character.

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The four characters of Chinese medicines are determined by their therapeutic effects on various disease. For instance, for cases with heat-syndrome manifested as fever, thirst, flushed face, conjunctivitis and rapid pulse, Gypsum Fibrosum(石膏）, Rhizoma Anemarrhenae（知母）, etc （such as White Tiger Decoction）are effective and they are considered as cool and cold in nature. While for cases with cold-syndrome manifested as chilliness, cold limbs, pale complexion and slow pulse, Radix Aconiti Lateralis Praeparata (制附子），and dried Rhizoma Zingiberis (干姜）etc, (such as Decoction for Yang Exhaustion) are effective, hence they are considered as warm and hot in nature. Applying medicines of different characters in line with syndrome differentiation is the key of clinical practice in traditional Chinese medicine.