Standardised herbal extracts seem to be popular – they are in many practitioner only herbal medicines as well as over-the-counter products. But based upon the questions I receive, few practitioners really understand what constitutes “standardisation” in Australia. As a result the Herbal Extract Company asked me to do a technical brochure which was released in early 2013, destined for practitioners and aiming to clear up some of the misconceptions and myths around standardisation.
What is the Australian Regulatory Definition?
The first thing to realise with standardisation of herbal products is that the Australian regulatory definition is rather loose. It basically revolves around whether an extract has a defined amount of a particular chemical constituent or group of constituents1.
The issue with this definition is that it is not really standardisation – at least not the way most people think of the word “standardisation”. It does not mean consistency between different products made from the same plant. And it certainly does not mean consistency of therapeutic effect.
Importance of Chemical Complexity
Research often demonstrates the therapeutic importance of a range of chemically unrelated constituents in many herbal medicines. Thus standardising for a narrow range of chemicals or single chemicals may not necessarily be of therapeutic benefit. For example, research indicates that the antidepressant activity of Hypericum perforatum (St John’s Wort) is due to more than just the hypericin content. However this is the only chemical commonly declared in standardised preparations in the Australian marketplace. The hyperforin and the flavonoids all appear to be important in the efficacy of this plant in depressive disease2,3.
Herbal medicines are biological entities – they are bound to vary from batch to batch. However there is a level of variation which is acceptable, and a level which is unacceptable. Real standardisation doesn’t just consider one or two chemicals, but it is a process which establishes quality through attention to details such as:
- seed stock
- chemotypes and genotypes (chemical and genetic variants of the one plant species)
- growth conditions
- harvest times
- processing methodology
- and finally the chemical profile
Interestingly we see some consistency between modern true standardisation and traditional quality control. When you read some of the real traditional herbal literature, you observe authors talking about the best locations for sourcing particular herbs, and the best time of the year and even time of the day to harvest.
Is Standardisation Good, or Not?
This is not a question with a single easy answer. In my clinical and technical experience, some standardised products are amazingly beneficial clinically, some are no better than a normal (and often less expensive) extract, and some are even less effective. What I look for in standardised products is:
- Does the company start with high quality raw material, or just blend batches of highly varying qualities and use excipients to “normalise” the final product?
- Does the company have research data, particularly clinical research, on their own extract, or are they just “borrowing” the research from another company and applying it to their own standardised extract?
- Does the company try to standardise the entire process from seed stock to growing conditions, harvest and extraction methods, and broad chemical profile, or do they just standardise for a single constituent?
It is not always easy for practitioners to find answers to the questions. However they are questions we should be asking our suppliers and manufacturers. After all, these are medicines and ethical practice comes with an obligation for us to use the most appropriate medicines for our individual patients. To do this, we must first understand them.
For more information on standardisation, contact the Herbal Extract Company for a copy of my technical brochure.
- Department of Health Therapeutic Goods Administration, 2013. Australian regulatory guidelines for complementary medicines. November 2013. <http://www.tga.gov.au/pdf/cm-argcm-131211.pdf> Accessed 2 January 2014.
- Cardellina JH, 2002. Challenges and Opportunities Confronting the Botanical Dietary Supplement Industry. Journal of Natural Products. 65:1073-1084.
- Braun L, Cohen M, 2010. Herbs & Natural Supplements An Evidence-Based Guide. 3rd Edition. Elsevier. p813-824