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Calligraphy of Chinese characters, meaning “Chinese
herbal medicine”
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Recent correspondence (PJ, 14 August, p221, and 28 August,
p287) has highlighted concerns about traditional Chinese medicines (TCMs),
particularly
the lack of quality control and quality assurance in the supply and manufacture
of preparations comprising Chinese herbal ingredients, and the lack of
reliable, objective information provided to users of these products.
Some TCMs have already caused serious health problems in the UK and other
developed countries and, despite initiatives from both the Medicines and Healthcare products Regulatory Agency (MHRA) and some representatives
from the Chinese herbal medicine sector, problems with the quality of
TCMs continue to arise.
Problems have been found both with finished products (known as Chinese
patent herbal medicines) and with herbal remedies made up by TCM practitioners.
This has led the MHRA to issue a new warning to inform the public and
health care professionals that some TCM products on the UK market may
be unsafe (p335). In addition, the MHRA has written again to the herbal
sector to remind and update interested parties of its concerns about
the quality of TCMs, and to seek co-operation in measures targeted at
addressing the problem and protecting the public health.
Current safety concerns
Over the past year, several new safety concerns about TCMs have arisen.
Some examples are given below, and further information is included
on the MHRA website.
Fenfluramine (an appetite suppressant prohibited since 1997 because
of concerns about its cardiovascular adverse effects) and nitrosofenfluramine
(which is hepatotoxic) were detected in samples of a product known as
Shubao Slimming Capsules, used to aid weight loss. A patient who ingested
this product developed irreversible liver failure and required a liver
transplant; the product was suspected as a possible cause.
High concentrations (11.7% w/w) of mercury, and trace amounts of other
toxic heavy metals, were found in a product known as Fufang luhuijiaonang.
The product was available in numerous TCM outlets across England and
steps were taken to recall it.
Human placenta and animal parts (deer antler and donkey skin) are listed
as ingredients on the patient information leaflet for a product known
as Nu Bao. The precise sources of these ingredients, and how they are
processed, are unclear, but their inclusion poses a risk of transmission
of infective bacteria and viruses.
Including any conventional prescription medicines (or other non-herbal
active substances) in unlicensed herbal medicines is illegal. However,
cases continue to be identified, for example, Chinese “herbal” skin
creams containing corticosteroids, Hua Fo tablets containing sildenafil
citrate and Xiaoke/Xiaoke-wan pills containing glibenclamide.
The most high-profile problems have included renal failure in women who
had ingested Chinese herbal medicines containing Aristolochia species,
which contain toxic and carcinogenic aristolochic acids. Aristolochia was prohibited from sale in unlicensed medicines in 1999. However, because
of poor or absent quality control, TCM products containing it still exist
and are found periodically in the UK.
A list of substances for which use in TCM has been restricted can be
found on the website of
the Register of Chinese Herbal Medicine.
Scale of problem unknown
It is not possible to estimate how many TCM products present a risk
to public health, and because they are sold as unlicensed products, it
is not possible to estimate how many types of products are sold on
the UK market through TCM outlets, TCM practitioners and other sources.
Equally, there is a lack of reliable UK data on numbers of people who
use TCMs.
The problem of poor-quality products is not limited to the UK. Reports
of adulterated or contaminated TCM products from other countries, including
Singapore, Taiwan and the US, indicate a global trade.
At present, there is no reliable way of identifying which products may
present a risk. There are examples of product labels listing ingredients
that are illegal in unlicensed products, as well as labels that fail
to declare such ingredients. Many TCM products are not labelled in English
and, generally speaking, this is a cause for concern.
The Royal Pharmaceutical Society’s Code of Ethics states that pharmacists
should ensure that their stocks of herbal medicines are obtained from
a reputable source of supply and that they should not recommend any remedy
where they have any reason to doubt its quality or safety. Pharmacists
who become aware of TCM outlets or other sources supplying any of these
products should inform the MHRA. Pharmacists’ role
Pharmacists can play an important role in protecting public health
with respect to TCMs and other herbal medicines (licensed or unlicensed),
including those from other traditional medical systems, such as Ayurvedic
medicines, some of which have also been found to be of poor pharmaceutical
quality. The MHRA, through the Herbal
Safety News section on its website, instructs consumers to inform
their pharmacist (or doctor) if they are taking herbal medicines with
other medicines and
to report to their pharmacist (or doctor) any adverse effects they
experience in association with using herbal medicines.
Pharmacists who are consulted by patients or the public about possible
adverse effects associated with TCMs should advise patients to discontinue
treatment and, depending on the nature of the suspected adverse drug
reaction (ADR), give appropriate advice or advise the patient to consult
their doctor. Pharmacists are encouraged to report suspected ADRs associated
with TCMs (and other licensed or unlicensed herbal medicines) to the
MHRA/ CSM using the yellow card
scheme. If possible, a sample of the
product and the packaging (or a copy) should be retained so that the
material can be tested if necessary.
Patients receiving prescription medicines, purchasers of OTC medicines
and others who consult pharmacy staff may be taking TCMs, so pharmacists
are encouraged to enquire about their customers’ use of herbal
medicines. The Chinese Medicine Advisory Service can assist pharmacists
with enquiries about TCMs (see panel).
Advisory service
The Chinese Medicine Advisory Service was
set up at the Medical Toxicology Unit, Guy’s & St Thomas’ NHS
Trust in 2001 to provide information on Chinese medicine to health
care professionals.
The
service aims to provide relevant information to improve understanding
of the benefits and risks of Chinese medicine and thereby enable
safe and appropriate use of Chinese medicine by patients. The
service includes identification of the raw herbs as used in Chinese
herbal
decoctions, translation of prescriptions and labels of products
supplied to patients.
We do not take enquiries directly from
consumers.
Contact Debbie Shaw, Chinese Medicine Advisory Service
(0207 771
5157; e-mail chimas@gstt.nhs.uk). |
Research at the “Square”
Work ongoing at the School of Pharmacy, University of London, is exploring
the availability and use of TCM in the UK, and issues related to
safety and pharmacovigilance of TCM products. |
The
Pharmaceutical Journal