Traditional herbal products are widely used in Australia to treat a broad range of conditions and diseases. It is popularly believed that these products are safer than prescribed drugs. While many may be safe, it is worrying that the specific effects and harmful interactions of a number of their components with prescription medications is not well understood. Some traditional herbal preparations contain heavy metals and toxic chemicals, as well as naturally occurring organic toxins. The effects of these substances can be dire, including acute hepatic and renal failure, exacerbation of pre-existing conditions and diseases, and even death. The content and quality of herbal preparations are not tightly controlled, with some ingredients either not listed or their concentrations recorded inaccurately on websites or labels. Herbal products may also include illegal ingredients, such as ephedra, Asarum europaeum (European wild ginger) and endangered animal species (eg, snow leopard). An additional problem is augmentation with prescription medications to enhance the apparent effectiveness of a preparation. Toxic substances may also be deliberately or inadvertently added: less expensive, more harmful plants may be substituted for more expensive ingredients, and processing may not be adequate. The lack of regulation and monitoring of traditional herbal preparations in Australia and other Western countries means that their contribution to illness and death is unknown. We need to raise awareness of these problems with health care practitioners and with the general public.
Unfortunately, some herbal products are problematic in terms of their ingredients, effects and interactions with prescription medications. Complications associated with “non-medically qualified healers, lack of product standards, undeclared ingredients, non-disclosure of usage and long-term medication” have been identified. A survey of naturopaths and Western herbalists in Australia has, however, revealed support for formal registration and for evidence-based practice. A report published in 2016 detailed the potentially serious side effects of herbal dietary supplements, such as sub-massive hepatic necrosis necessitating organ transplantation caused by ingestion of a weight loss supplement containing garcinia cambogia (Garcinia gummi-gata).
We undertook a literature review after searching general internet and PubMed databases for selected terms and combinations of terms, including “adverse event” and “herbal”, “complementary and alternative medicine” (CAM) and “Australia”, “dietary supplement”, “traditional Chinese medicine” (TCM), and “ayurvedic”, as well as more specific clinical terms, such as “hepatotoxicity”. We examined the range of problems that may be encountered with preparations containing herbal materials, in order to determine the nature of the risks they pose to the Australian public and to make recommendations about their regulation.The authors conclude
While there is no doubt that prescription medications are responsible for many serious side effects and deaths in Australia every year, this should not distract us from trying to determine the contribution of herbal preparations to morbidity and mortality. Although herbal products are claimed (especially on social media sites) to be completely safe, it is difficult to understand why it is widely believed that preparations with biological activity would not also have the potential to cause medicinal side effects. Light touch regulation of the industry means that dosages can be inconsistent, contents inaccurately listed, and toxic and pharmaceutical contaminants and adulterants may be present in herbal medicines.
Rather disturbingly, the answer to the question we asked at the beginning of this discussion — what are the risks to the Australian community from herbal products? — is that we simply do not know. This is a far from satisfactory situation, and perhaps one to which state and federal governments and regulatory bodies, including the TGA, should respond with greater urgency. We would certainly support more widespread testing of products and policing of label and website inaccuracies, although this will require financial support from an already stretched health budget. It may be appropriate for the TGA to require manufacturers to have samples independently tested before placing them on the market. Legal action should be considered in cases of non-compliance with applicable regulations, and preparations containing illegal substances should be banned. How many more adverse drug reactions involving herbal products are needed before more attention is given to this important public health problem?