Dosage Considerations of Extract Powders and Granules
One of the common questions from clinicians to our consultants is about recommended dosages for our extract powder formulas and single herbs. To provide a foundational knowledge of the nature and characteristics of extract powders and granules, please see my other article in this month’s newsletter. In that article, I define the difference between extract powders and extract granules, whether extract powders/granules are “concentrates” or “concentrated”, what the popular designation “5:1” means when referring to extract powders/granules, various factors that affect yield, and how and why excipients/fillers/diluents are used in their production.
Since most TCM herbalists received their initial training with whole (or raw) herbs, the question is often phrased as: “What is the extract powder dosage equivalent of single herb extract compared to a whole herb (or formula)?” After several discussions with our manufacturers and other experts in the production of extract powders/granules, I regret to report that there is no bona fide equivalency. This is because the various methods of herbal prescribing, e.g. whole herb decoctions, extract powders and granules, draughts, tablets, tinctures, and various types of pills, etc., feature dosages that do not lend themselves to any easy calculation of equivalency. Mostly, clinicians must depend on their herbal training and experience and, in large part, on the dosage recommendations from the product manufacturer to determine a therapeutic dose. Regardless of the form of administration, the clinician is expected to adjust dosages based on several factors, most of which are clearly described in Laura Stropes’ article in Mayway’s March 2018 newsletter.
History and Evolution of the Use of Decocted Extract Powders
In Japan, extract granules developed into an important part of Kampo medicine in the 1950s. Kampo (Kanpō 漢方) is based on ancient Chinese herbal formulas, especially those from the Shanghan Lun (Han Dynasty) and Hejiju Fang (Song Dynasty). Kampo formulas are highly standardized and often composed of 4 to 9 herbs. Dosages were usually relatively small (for many theoretical reasons): between 2 to 6 g per day.
A short time later, Taiwan began using extract granules instead of home-prepared decoctions, mostly because of their convenience for patients. However, in Taiwan, in keeping with the development of the use of Chinese herbal formulas during the Yuan, Ming, and Qing dynasties, the formulas contained a larger number of herbs and the dosages prescribed were often three times higher than those in Japan. Depending on the formula, dosages were often 12 to 18 g per day. It is reported that the National Health Insurance (NHI) in Taiwan will pay for up to 24 g per day.
When extract granules first appeared in the United States in the late 70s and early 80s, most companies recommended a dosage of 6 g a day. Today, various sources suggest a range of dosages from 3 g to 18 g per day. Generally, larger dosages are associated with acute conditions and smaller doses with chronic conditions, especially when deficiency is involved, and long-term therapy is indicated. Other considerations include the size of the original formula in terms of the number of the herbs or total grams and not surprisingly, the actual yield ratio of the formula. Formulas with “higher” (poorer) yield ratios, for example 8:1 or 10:1, may require a higher dose. Just as Laura Stropes pointed out in her article from 2018, practitioners truly must rely on their clinical experience and assessment.
In researching published data for this article regarding dosages for our extract powders/granules, I discovered that several manufacturers do not specifically state a recommended dosage for these products on their website or labels. Likewise, various authors and teachers recommend a wide range of dosages.
Extract granule products, which contain excipients/diluents (e.g., dextrin, malto-dextrin, starch, or sugar), certainly require the consideration of a higher dose. Since these granules are 30-60% excipient, one can understand why the doses in Taiwan are so much higher. However, please note, the published, standard dose for Mayway extract powder formulas (which contain no excipients) is 3 g, three times per day or 4.5 g, twice a day.
Let’s look at an example of recommended dosages for the classic formula for kidney yin deficiency Liu Wei Di Huang Tang, according to Bensky’s Formulas and Strategies:
(* Note: When using Plum Flower® Liu Wei Di Huang San (100% extract powder), the percentages represent the percentage amount of the herbs in 1 g, 9 g, 75 g, or 100 g, regardless.)
Using Mayway’s dosing guidance, if you wanted to dispense a weeks-worth of Liu Wei Di Huang San at 4.5 g, twice a day, this would make a total of ~64 g to be dispensed. Or put another way, a 100g bottle of this formula would provide sufficient dosage for about 11 days.
Using other companies’ extract granules, which contain at least 30% excipient, you would need to dispense 91 g, and have the patient take 6.5 g twice a day to achieve an equivalent dose to Mayway’s pure herb extract powder. Using extract granules, a 100 g bottle will last nearly 8 days, and if the granule product contains more than 30% malto-dextrin, you will need to increase the dose accordingly.
Tailoring (jiājiǎn加減) Extract Powder Formulas
When tailoring a traditional formula or when creating a custom formula that is not necessarily based on a traditional formula, there are a couple of considerations that need to be addressed when tailoring formulas with single herb extract powders/granules.
First, the little spoon, sometimes called a “gram spoon”, which is dispensed with these formulas and which has great practicality for patients, is not necessarily equivalent to a gram. Really, it depends on the density of the extract powder or granule product. In the dispensary, a scale capable of accurately measuring grams is required.
The second issue also relates to powder densities and/or granule size. Ideally, every dose or spoonful of the finished product would be the same as every other dose. This requires significant mixing since differences in particle size or density will result in a heterogeneous mixture if not thoroughly mixed. Most dispensaries, whether in a practitioner’s office or in a school of TCM are not equipped with a mixer capable of performing this task satisfactorily. Stirring the extract powder/granule mixture in a bowl with a spoon or to shaking it in a bottle or plastic bag is not sufficient. In Mayway’s GMP-compliant dispensary, we use a Turbula®, which is a professional mixer that tumbles the tailored formula in three dimensions, for at least 10 minutes.
Now, let’s discuss how to construct a tailored formula with which one wants to add a couple of herbs not in the original formula. In general, I have observed that nearly everyone adds single herbs to a tailored formula at far too low a dose. I have noticed when most clinicians add a single herb to a formula that they usually add 2 or 3 g, sometimes as much as 5 g, but rarely more than that.
To illustrate how to add herbs to an existing formula, let us look again at Plum Flower® Liu Wei Di Huang San (100% extract powder) in the box above. This formula is the classic formula for tonifying the Kidney Yin. Suppose I want to add two herbs that supplement the Liver and Kidney Yin and Cool the Blood. For example, Han lian cao and Nu zhen zi. This herb couple is often added to a decoction at 9 g each in each bag of whole herbs.
The simplest solution for adding these two herbs is to look at the original whole herb formula and note that three of the herbs are also dosed at 9 g per bag of whole herbs.
These three herbs appear in our weeks-worth of extract powder as 12% of the total formula and 8 g in 64 g for the week. Therefore, I would first consider adding 8 g of both Han Lian Cao and Nu Zhen Zi to the formula, per week of dosage.
The Plum Flower® single herb extract powders contain dextrin (as differentiated from the formulas, which do not contain excipients). Therefore, the dosage must be adjusted to account for this to maintain the correct herbal ratio in the formula.
Like all single herbs and formulas made in extract granule form, each Plum Flower® single herb extract powder contains a different amount of excipient depending on production requirements for each herb. Since the exact amount of excipients in each batch varies, for ease of calculation, I will assume that the amount of excipient equals 10%, which is the average amount Mayway uses to provide free-flowing powders that are shelf stable.
To keep the formula balanced, I will need to add 9 g of extract powder for each single herb that I am adding to the extract powder formula. This results in a total formula of 82 g for one week and my new dosage will be just under 6.0 g twice a day.
By contrast, if other companies’ extract granules are being used, then you may assume that the amount of maltodextrin is at least 30%. In this case, divide the number of grams in the third column by .70 (1.00-0.30) to determine how many grams of granules to use. For example, if 8 grams are called for, then the amount of extract granule necessary will be 11.5g (8/.70), with an appropriate increase in the dose per day.
Creating Custom Formulas from Plum Flower® Single Herb Extract Powders
Jiājiǎn means “addition and subtraction”. Sometimes this means that you cannot start with a traditional formula product because you cannot “subtract” herbs from a finished product. Many studies that reference Chinese herbs do not publish dosage amounts for each herb, only the names.
So, the creation of a custom formula is necessary. If you want to use extract powders/granules, this is what I recommend:
- Write the custom formula as if you were constructing a whole herb formula. (For an in-depth review of formula writing, you may wish to avail yourself of Mark Frost’s course “Advanced Herbal Prescription Writing”.)
- Consult a Materia Medica that indicates the usual dosage range of each herb.
- Weight each of the herbs according to their position/function in the formula.
- Add your own experience and ideas, then assign dosages of each herb in the formula.
- Total the number of grams of all the herbs.
- Calculate the percentage of the total that each herb contributes to the whole.
- Decide how many grams the patient should take each day and multiply that number by seven to determine how many total grams to dispense for a week.
- Multiply the total grams for the week by the percentage of each herb in the custom formula. This will indicate how many grams of each herb would be in the formula if there were no excipients.
- Dispense as written or consider increasing the dosage by ~10% if using Plum Flower® single herb extract powders and by ~30% if using extract granules from another company.
I realize that what I am suggesting may seem like a daunting task and requires a bit of math, but there is no simple rule of thumb that I have discovered. We, as practitioners, want to be adept at creating the most appropriate formula in a reliably efficient manner. Using these methods, I think you will achieve a higher quality herbal extract formula and better therapeutic outcomes.
As I mention in my other article, extract powders/granules are optimized, dried decoctions, akin to instant coffee or hot cocoa mix. As practitioners, we use them with the expectation that they are relatively equivalent to a decoction, and it may be useful and interesting to reconstitute a single dose in a cup of water and compare it to a decoction made from whole herbs. If the reconstituted “tea” appears to be “thin” (in color, aroma, or taste), then this is probably not an effective dose when compared to a traditional herb decoction. Just as you can readily tell if a cup of instant coffee is “too weak“ or “too strong”, the same observation will hold true with reconstituted herbal extract powder formulas. Watch our video of what happened when we compared the same formula from 6 different brands.
In addition to the author’s experience and interviews with Mayway’s consultants and manufacturers, the following resources were consulted:
- Bensky, D., Formulas and Strategies
- Chen, J., Chinese Herbal Applications
- Brand, Eric, A Clinician’s Guide to Using Granule Extracts
|Bio: Skye Sturgeon, DAOM, L.Ac.
Skye is the Quality Assurance Manager and Special Consultant for Mayway, USA. Skye was the former Chair of Acupuncture & East Asian Medicine and core faculty member at Bastyr University, core faculty member and Faculty Council Chair at the American College of Traditional Chinese Medicine, and President and Senior Professor of the Acupuncture & Integrative Medicine College, Berkeley. Before making Chinese medicine his career choice, Skye held various positions in the Natural Foods Industry for 12 years and prior to that was a clinical biochemist and toxicologist.