Herbal medicine: advocates need to put things right

Abstract

Response from ErnstI am encouraged by the interest in my recent TiPS article [1xToxic heavy metals and undeclared drugs in Asian herbal medicines. Ernst, E. Trends Pharmacol. Sci. 2002; 23: 136–139Abstract | Full Text | Full Text PDF | PubMed | Scopus (260)See all References[1]. In their letter to TiPS, Izzo and colleagues point to the important issue of herb–drug interactions. Potentially, this concerns a very long list of medicinal herbs [2xPossible interactions between synthetic and herbal medicinal products. Part 1. A systematic review of the indirect evidence. Ernst, E. Perfusion , 4–6. 2000; 13: 8See all References[2]. The subject clearly requires more research, which, in turn, begs the question who should fund such research? A recent unpublished survey by my team indicated that neither the pharmaceutical nor the herbal industry is inclined to take on this responsibility; this suggests that governments should assume responsibility but, sadly, I do not see signs that they are.In the letter by Shi-Sheng Li, the author makes several interesting points. Regulation of herbal remedies differs from country to country. Few experts would disagree with the verdict that, in the West, they are grossly under-regulated. I am well aware of the fact that herbal medicines have been used ‘for several thousands of years’. I am, however, also aware of the fact that this test of time is no substitute for compelling data on either efficacy or safety – in fact, there are numerous examples of herbal (or other) therapies that were found to be ineffective or unsafe or both after having been in use ‘for several thousands of years’ [3xTraditional remedies and the ‘test of time’. Ernst, E. et al. Eur. J. Clin. Pharmacol. 1998; 54: 99–100Crossref | PubMed | Scopus (32)See all References[3]. It is true that according to Chinese and Ayurvedic traditions heavy-metal-containing herbal mixtures are ‘processed…to minimize their toxicity’ but, as my article shows, this does not stop them from harming patients. In other words, the procedure of rendering toxic metals non-toxic is not effective. My article also refutes that such traditional medicines are ‘restricted to external use’. Virtually all the adverse events happened after oral administration.It would be wrong to understand my review as a general damning of Asian remedies. The point I tried to make is that, as long as serious adverse events occur with some regularity, something must be amiss. It is up to those who promote these treatments to put things right.