Evidence

Is there adequate evidence for plant medicines?

Some medical doctors fear that botanical drugs lack convincing evidence, citing fears of drug-herb interactions, poor quality of plants and potentially harmful side effects, although a growing number of doctors are eager to integrate botanical medicines into their patient healthcare plans. In Europe, clinical research into herbal medicines has been established for decades, particularly in Germany, where phytotherapy is an accepted part of medical practice (Rotblatt and Zimmett, 2000).

Although a plant is natural it does not always mean that it is safe. That is why degree-educated medical herbalists in clinical practice adhere to providing herbs from excellent and reputable suppliers that can approve a high level of assurance that the products supplied, via scientific validation methods, meet strict standards in safety, quality, and efficacy. Current scientific paradigms of randomised clinical trials (RCTs) where isolated constituents are tested for pharmacological efficacy do not work from an herbalist’s perspective where the whole herb is used for better clinical results, although research into isolated plant chemicals is of great importance having given rise to many of the world’s most useful drugs such as morphine, aspirin, and digitalis.

According to the WHO (1998), “Experience has shown that there are real benefits in the use of whole medicinal plants and their extracts since the constituents in them work in conjunction. However, there is little research on whole plants due to the drug approval process not accommodating undifferentiated mixtures of natural chemicals. To isolate each constituent from each herb would be immensely time-consuming at unsupportable cost”.

This does not mean there are no RCTs supporting the use of plant medicines. A review of Pubmed and the Cochrane Collaboration includes positive RCTs and Met-analyses for herbs such as Gingko for cognition and dementia, Echinacea for immune health, St John’s Wort for mild to moderate depression and Feverfew in the treatment of headaches and migraines.

Traditional and historic evidence.

There is much historical information on the use of phytotherapy in classical medical botanical texts, pharmacopoeias, academic books, and monographs to inform clinical practice.

Bone (2000) states “The important point is that traditional herbal medicine use is the refined knowledge of many generations around the world, carefully evaluated and re-evaluated by many practitioners of the craft. It is not just the anecdotal accounts of a few practitioners”.