are monitored closely. The European Agency for the Evaluation of Medic-
inal Products in London has a working party on herbal medicinal products,
with the remit to include pharmacovigilance and the introduction of safety
measures throughout member states. The MHRA performs a similar task in
the UK. Currently, Chinese herbal suppliers are engaged in agreeing guide-
lines to ensure that their medicines are of the highest quality and free from
adulterants.
The RCHM introduced a system of approving suppliers in 2002, where
companies are required to submit themselves to an independent audit by a
trained pharmaceutical auditor.
The audit examines the quality system of the UK supplier and focuses on
the five Ps of GMP: premises, personnel, products, procedures and processes.
The company is then inspected at yearly intervals.
Although still in its infancy, this approved suppliers’ scheme has
provided a framework for future initiatives to increase confidence in the
quality of Chinese herbs and herbal products.
The aristolochia story – a complex problem^180
Severe concerns about the safety of the herb Aristolochia arose in early
1992, when two women presented with extensive interstitial renal fibrosis
to doctors in a Belgian clinic that specialised in weight-loss regimens. The
condition rapidly progressed to terminal renal failure.^181 The total number
of patients exposed to the herb is not known exactly, but around 100 people
with renal disease were eventually recorded, representing about 5% of those
who took the slimming preparation.^182
The diet regimen used by the clinic for many years without problems
comprised a mixture of acetazolamide, fenfluramine, and various animal and
vegetable extracts. In the mid-1990s the formula was supplemented by the
addition of powdered extracts of Chinese herbs. A possible relationship
between the renal disease and the herbs was suspected. Subsequently, it was
established from an epidemiological survey that Stephania tetrandra was the
only herb associated with all the cases of renal disease. Most unexpectedly,
the alkaloid normally derived from Stephania – tetrandrine – could not be
found in the capsules taken by the affected patients.^183 Instead, analysis
revealed the presence of a series of substituted nitrophenanthrene carboxylic
acids, known as aristolochic acids. These were considered to be the cause of
the adverse reactions.184,185 The acids form the main active principle of
various species of another Chinese herb, namely Aristolochia.
It was finally concluded that the Stephania tetrandra (han fang ji) must
have been inadvertently replaced by Aristolochia fangchi (guang fang ji) in
the powdered extracts delivered to Belgian suppliers. Herbal ingredients are
usually traded using their common Chinese names and this can lead to
confusion during translation. About 185 kg of the substituted han fang ji
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