Problems With Plant Remedies?

Although many modern drugs have been derived from herbal remedies, it should come as little surprise that Canter and Ernst (the Peninsula Medical School, Exeter) have published a study suggesting that 'bespoke' herbal remedies for individual patients may do little good and may carry significant risks (http://www.guardian.co.uk/medicine/story/0,,2183054,00.html). These 'remedies' are cocktails different herbs concocted for individual customers and can contain extracts from up to 20 different plants. The market in 'over-the -counter herbal medicines' was worth £191m in the UK last year (this, of course, includes numbers of single plant derived preparations) and there appears to be considerable enthusiasm in some circles for such 'holistic' treatments. The thing to remember is that these preparations are not subject to rigorous testing (claims that studies on the efficacies of individualised herbal remedies have "only recently been started" seems a bit odd- one would normally expect trials before treatment) , may vary greatly in terms of their concentrations of contained chemicals and are generally complex mixtures of components (this is especially true of the 'bespoke herbal concoctions). All these characteristics make effective testing very difficult. Canter and Ernst suggest that the herbal preparations are linked, in some cases, to side-effects (e.g. liver toxicity in the case of Kava kava and possible increased risk of brain haemorrhage in the case of Ginko bilboa). Some herbal preparations have apparently been found to contain traces of prescription drugs or even agrochemical contaminants. In deed, some components of the herbal cocktails can interact with drugs prescribed by medical doctors (e.g. Saw palmetto can interact with aspirin or Warfarin to increase bleeding as well as interfering with the contraceptive pill). It appears very important that people be made aware of the need to tell their doctors about their ingestion of herbal remedies. There is also a clear need for the herbal remedy market to be more tightly regulated and the practitioners to work a bit harder on their evidence base.