The temporary ban on the inclusion of aristolochia species in herbal medicines is to be extended to include herbal ingredients that can be confused with aristolochia species.
A recent sampling exercise found that 44 per cent of samples at risk of confusion with aristolochia contained aristolochic acids.
Aristolochia species are considered to pose a serious risk to public health because aristolochic acids are mutagenic, carcinogenic and cause kidney damage.
The ban is felt to be necessary because a number of plants have similar common or Pin Yin names, or because Chinese herbal tradition allows the interchange of plants with similar medicinal properties.
The ingredients which it is proposed will be banned are Akebia quinata, A trifoliata, Clematis armandii, C montana, Cocculus orbiculatus, C thunbergii, C trilobus and Stephania tetrandra and their extracts. In addition, Chinese herbs described as Mu Tong or Fangji are to be banned, along with their extracts.
Comments on the proposed ban can be sent to Mr Paul Brittain, Medicines Control Agency, Room 619, Market Towers, 1 Nine Elms Lane, London SW8 5NQ by February 17.
The MCA believes that the ban is necessary, not because the additional species are dangerous in their own right, but because products containing them could contain aristolochia.