Media Update Regarding Recent Herbal Arbutin Regulation
You may have heard that there has been some recent changes to the allowable levels of Arbutin in your clinical herbal formulas. However, it would perhaps be more accurate to state that some long standing regulations (since 2010) surrounding the allowable Arbutin levels in herbal medicines, have recently become more proactively enforced by the Therapeutic Goods Administration (TGA).
In order to assist you with being informed on this issue, as well as aware of your compliance obligations in practice, please consult the following summary.
Arbutin is an active compound found in numerous plants, but most notably the following:
- Arctostaphylos uva-ursi (Bearberry)
- Achillea millefolium (Yarrow)
- Chimaphila umbellata (Umbellate Wintergreen / Prince’s Pine)
- Kalmia latifolia (Mountain Laurel)
- Ledum palustre (Wild rosemary)
- Origanum majorana (Marjoram)
- Pyrus communis (Pear)
- Pyrus pyrifolia (Asian pear)
- Rhododendron ferrugineum (Alpine rose)
- Turnera diffusa (Damiana)
- Vaccinium vitis-idaea (Lingonberry leaf)
Arbutin may theoretically convert to Hydroquinone in the Liver or Gut and circulate within the body (via certain metabolic interactions with gut flora). However the degree to which this occurs in numerous scenarios in humans has not been fully demonstrated, and the amounts of Arbutin in most of the above plants remains relatively small.
Hydroquinone is sometimes used within skin whitening products overseas (due to its inhibition of enzymatic Melanin hyper-pigmentation) in concentrations of 2%, and sometimes 4% in prescription-only topical formulas, however it has been banned for OTC cosmetic use by the European Union in 2001, due to a potential carcinogenic toxicity risk indicated in animal studies.
The TGA has responded to this concern on behalf of Australian citizens by conservatively limiting the allowable amount of Arbutin in Listed Complementary Medicines to the lowest acceptable equivalent level of Hydroquinone shown in those studies (equivalent to 0.001%), even in cases where the above herbs are to be taken orally for other purposes (such as for digestive antimicrobial effects).
This very low threshold means that any plants with notable levels of Arbutin, in particular Uva Ursi (Bearberry), which may commonly include levels around 6-7% in standard dried leaf material (albeit only making up a smaller portion of any final formula), should not be prescribed or supplied by Australian Natural Therapists until any further regulatory changes are made (as the use of such concentrations has technically not been compliant since 2009 on this basis).
This includes Extemporaneous Herbal Compounding (e.g. Tinctures), which although not requiring an AUST-L number, cannot employ the use of any ingredients scheduled as an S4 (which is restricted for medical prescription use only), which ingredients with above levels of Arbutin must now be classed under.
A submission to the TGA is being prepared by the CMA to propose increasing the allowable limit slightly (to 0.0025%) on the basis of the theoretical Arbutin conversion to Hydroquinone not being a 1:1 conversion. This may be the quickest way of ensuring that more of the herbs on the above list can avoid restriction (however it leaves much more time and research required in order to demonstrate that any of the higher levels found in Uva Ursi or other concentrated formulas can be made safe and appropriate for Australian Practitioners to use).
Please therefore note that until such research has been conducted (and does indeed demonstrate an acceptable level of safety to the TGA), it may not be appropriate to campaign for further changes on the immediate steps being taken by the TGA to follow through on this matter.
We trust this assists your ongoing awareness and understanding of current matters affecting your Practice, and will update all members as soon as any notable changes occur.