Do Herbal Remedies Really Work?
From Traditional to Modern Medicine.
While physicians of old and modern practising medical herbalists depend on traditional knowledge – based on observation on patients and information passed on through teaching, modern medicine demands evidence derived from controlled clinical trials (CCT) before prescribing.
Only a few of the herbs in the Physic Garden (less than 10%) have been investigated in this way. Since many people are turning to herbal remedies in the 21st century there are new initiatives to conduct controlled clinical trials. Funding for such trials is hard to obtain since for obvious reasons the pharmaceutical industry is not interested – herbal extracts cannot be patented unless in some way modified, and taking any single chemical through to clinical trials requires major preclinical testing (eg animal research).
Controlled Clinical Trials (CCT)
A controlled trial of a new medicine consists of enlisting people, with a disorder diagnosed according to strict consensus criteria, into a study in which two similar randomised groups of patients are given either the agent to be tested or a placebo (an inactive agent). Neither the patient nor the clinician is aware of which group is on which (double blind). The trial is conducted on sufficient numbers to give statistical power (i.e. to allow for significant data) and for long enough to override the placebo effect (generally more than three months and up to a year). Positive results from one such trial are not generally considered sufficient to provide guidance /regulatory approval, and ultimately evidence is gathered from several independent clinical trials providing a meta- analysis.
Herbs with Positive CCT Evidence
Herbs growing in the Dilston Physic Garden which are considered to have reached or are moving towards this standard of clinical evidence (for whole herb preparations – dried herb capsules, liquid extracts or essential oils for example) include:
|
|
Updated 2008 EKP DPG
NOTE – it is advisable to consult a Medical Herbalist before taking herbal medicines and to check, if you are also using licensed drugs, about possible interactions.