Introduction - Uppsala Monitoring Centre

The second category of herbs was called medium or medicinal
and were used to rectifying imbalances in the human body. These
were used until the patient recovered from their illness and then
withdrawn, e.g. ephedra (Ma Huang) and dried ginger.
The third category of herbs was called inferior or radical herbs
(e.g. croton) (Croton tiglium) which helps to relax the bowels, relieve
oedema (swelling) or eliminate, ‘so named because they are strong
in action and not without side effects; sometimes they are toxic.
Therefore these were used often in small amounts and once the
desired action took place they were discontinued immediately.’ e.g.
Rhubarb, aconite, arsenic sulphide, mercuric sulphide and
earthworm.(Maoshing Ni, 1995).
The concept of ‘side-effects’ is not recognised as such in Chinese
medicine. The toxic effects of certain medicinals are recognized
according to degree, and if it is necessary to use a ‘toxic’ substance
medicinally, it will be prepared in a special manner or combined with
other medicinals to reduce or eliminate toxicity if possible
(Rosenberg, 1997). The difference between ‘side-effects’ and ‘toxic
effects’ in this context is rather obscure. Most non-Chinese toxicity
data are not related to the intact Chinese medicine, but to their
specific, presumed active chemical constituents, which are generally
irrelevant to the toxicity one seeks for any particular traditional intact
medicine (Leuang, 2006). This implies either that there are
components in the intact specimen that interact with the known
active constituent to alter the toxicity, i.e. an interaction or that the
preparation of the intact specimen alters the toxicity.
The Chinese meaning of ‘toxic’ should not be equated with the
western connotation. ‘What are recorded as toxic drugs only apply to
those that have been found over time to be consistently toxic, though
in different degrees, when used in the traditional manner. There are
countless others that ordinarily are not toxic but may be toxic if used
outside of tradition.’ (Leung, 2001).
www.phyto-tech.com/lchn/2001-0102.html (accessed 16 th November
2009). I have not been able to find out how a herb is classified as
‘toxic’. The many anomalies baffle me, e.g. arsenic disulfide–nontoxic,
honeycomb–toxic. The ‘ShenNong BenCao’ has a phrase
‘Take mercury over a long period, you will become a celestial being
of immortality.’
‘Toxicity can be reduced by proper processing, or by adding
another herb to counter the toxicity.’ (Zhu, 2002). This reference to
interactions is further explained by Paul Unschuld as 7 categories: