Intrinsic toxicity of herbs
Some CHMs have already caused serious health problems in the UK and other
developed countries and, despite initiatives from both the MHRA and some
representatives from the Chinese herbal medicine sector, problems with the
quality of CHMs continue to arise.^166
Large amounts of traditional medicines are imported into the UK, legally
and illegally, and use of such medicines is frequently not admitted on occa-
sions when serious illness forces patients to consult western medical practi-
tioners. These medicines carry with them a risk of adverse reactions; the risk
needs to be quantified and as far as possible minimised. A correspondent to
the Pharmaceutical Journalhas expressed concern that the availability of
traditional CHMs in the western world will, at some time in the future, pose
serious problems.^167
A warning that there can be no guarantee of the safety or quality
of traditional CHMs was issued by the MHRA in 2004 (http://tinyurl.com/
2olbvg), following a similar warning 3 years before. The warning was circu-
lated again in the light of clear evidence that problems with traditional CHMs
containing toxic, and often illegal, ingredients persist, with the ingredients not
always being declared on labels.
The MHRA said:
There is no reliable way for the public to identify those CHMs which
could be unsafe. In the light of this evidence we are unable to give the
public any general assurances as to the safety of CHMs on the UK
market. When buying TCMs people should always be aware of the
possibility of low quality or illegal products. They should not take
them if they are not labelled and [do not] include a list of ingredients
in English. Even then, clear labelling is not in itself a guarantee of
good quality standards.Other general and specific safety warnings associated with the use of CHMs
may be found at http://tinyurl.com/2p6rp4.
The herbs prescribed by practitioners of TCM in the UK are generally
purchased from wholesale companies that specialise in this trade. These
companies import herbs from the People’s Republic of China either
directly or through dealers in Hong Kong. The quality of imported herbs
varies considerably, and great skill is needed to ensure that the correct
herbs are provided to the practitioner. Some substitution of herbs is
acceptable in China but can lead to problems if the wholesaler or practi-
tioner is unaware of the substitution (see below). Confusion may arise
over the precise identity of the herb being ordered; no standardised
nomenclature exists for herbs. Fortunately, the best wholesalers and
Traditional Chinese medicine | 163