by Eric Brand

In previous blogs, I have written about granule preparations and global trends in their clinical use. Invariably, the issue that seems to be the most challenging to practitioners is dosage. To a certain extent, the challenge of dosage is compounded by a widespread lack of transparent labeling in the industry, an issue that has also been raised in past blogs. Many suppliers do not provide data that relates the extract powder to the quantity of raw herbs that went into it (the concentration ratio), so estimating the desired dosage for a given case can be a challenge in the absence of clear labeling or extensive clinical experience.

Another challenge with dosage relates to medicinals that cannot be concentrated. Not all substances used in Chinese medicine were traditionally taken by decoction, and the decoction process is not suitable for certain items that have delicate or insoluble active constituents. To evaluate the clinical use of such medicinals, it is best to assess individual examples so that one can clearly see the various issues in play.

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Most items that we use in clinical Chinese medicine are plant products, though animal and mineral products are also part of our arsenal. Plants are typically the easiest substances to produce as a concentrated extract; mineral and animal products often require slightly different techniques. The maximum potential concentration ratio that can be achieved varies from one medicinal to the next, largely based upon the type and quantity of water-soluble constituents present in that medicinal. Additionally, excipients are generally needed to prevent clumping, which dilutes the concentration of the final product. The amount of excipient required varies depending on the form of the final product and the type of excipient that is used. See this blog to learn more about excipients

On the subject of basic potential concentration ratios, a few generalities can be made. For example:

Many vine and stem products have a high crude weight relative to their water-soluble constituents, so they can often achieve very high concentration ratios. For example, Zhu Ru, Da Xue Teng, Ji Xue Teng, Ren Dong Teng, and Ye Jiao Teng can achieve concentration ratios ranging from 15:1 to 25:1.

Many sticky, polysaccharide-rich medicinals achieve lower concentration ratios. Examples include Huang Qi (5:1), Gou Qi Zi (3:1), and Dang Gui (3:1).

Many minerals cannot be concentrated, and all gelatin products cannot be concentrated.

Animal shells and other difficult to extract products are generally more potent when used in a granule form, because home extraction is comparatively less efficient.

Many insect products are desirable in granule form. While some insects were traditionally taken as a powder, many are used by decoction. Insect products are more hygienic and convenient in granule form, and they often achieve significant potency. For example, Chan Tui (cicada shells) and Di Long (earthworm) can generally achieve a high concentration ratio (10:1 or higher), and each of these items can be problematic for patients decocting medicinals at home. Toxic items like Wu Gong (centipede) and Quan Xie (scorpion) benefit from a controlled processing method and testing regime, but their use requires transparency on concentration ratios for safe dosing. These two items typically range from 2:1 to 5:1 in most finished products, but it is always best to check with your supplier to be sure. Interestingly, one large scale study in China found that the clinical results when using insect medicinals were better in the granule group compared to the decoction group.

General dosage information

If one is mixing a formula from single herb extracts, a total target dose of around 12-18 grams per day is usually considered suitable for most cases. The dosage of each individual medicinal tends to vary based on its potency and nature. While transparent labeling provides greater precision, most single medicinals tend to be used at a dose range of 0.5 to 3.0 grams per day. Often, this dose range is mathematically a bit lower than the corresponding raw herbal dosage, but the increased efficiency of extraction that a controlled setting provides generally allows for a slight reduction in overall raw material weight. Additionally, other factors play a major role in determining dosage, such as the intensity of the case and the number of ingredients in the formula, as well as the potency of the herbs and the relative emphasis of their principles.

Just like when using raw medicinals by decoction, each item has its own dose range when prescribed as a granule extract. It can be useful to group the items into low, middle, and high dose ranges, though one’s thinking should always be flexible in response to the case.

Items that are potent by weight and have a lower standard dose range are often prescribed in doses of 0.5 g/day or even 0.3g/day; examples include items such as Rou Gui or Wu Zhu Yu.

Average items are often used at a dose of 1.0-1.5 g/day; examples include Bai Shao, Bai Zhu, and Fu Ling.

Medicinals that are weak by weight require larger doses, often 2-3 grams per day or even more; examples include Yi Yi Ren and Shan Yao.

Items that cannot be concentrated

Some items cannot be concentrated. Although many of these items are stocked by granule suppliers, virtually all of the companies sell a ground powder rather than a concentrate. The reason that an item cannot be concentrated varies depending on the medicinal, and its dosage in granule preparations always depends on the traditional method and dosage of the substance itself.

When prescribing these medicinals, one must generally choose whether or not to preserve their traditional dosage in the granule form. Many of these items have been known to be less effective in decoctions for a long time, so they were traditionally taken as a powder. Since most of them have a moderate dose range of 1-3 grams, they can easily be taken at this same traditional dose along with other granules.

For items that were traditionally used at higher doses, such as gelatins, one has to make a choice. One can either increase the size of the total granule prescription dramatically to accommodate the traditional dose, or one can use a lower than normal dose of the non-concentrated item. The latter choice is often used when cost is a factor in the treatment; this is sometimes an outside constraint that complicates the decision-making process.

Allow us to consider some examples of items that are not concentrated:

San Qi has delicate constituents that are damaged by heat, so prolonged cooking negatively impacts its blood-stanching ability. However, it is traditionally considered best when taken as a powder, so actually the dosage used is the same.

Chuan Bei Mu is too expensive in its authentic form to make a granule extract affordable. Various products from related species (thought to have similar actions but reduced efficacy) are often used as substitutes when preparing concentrates. However, most companies simply supply authentic Chuan Bei Mu as a 1:1 (non-concentrated) product rather than an extract.

Xi Yang Shen is the same as Chuan Bei Mu, sold as a 1:1 powder because of its expense (it also has delicate constituents). Like Chuan Bei Mu, Xi Yang Shen was traditionally taken as a powder rather than by decoction anyway.

E Jiao, Gui Ban Jiao, Lu Jiao Jiao, and Bei Jia Jiao are animal gelatin products, and they cannot be concentrated because they are effectively already concentrates. Further boiling just causes them to stick like glue in the machines, and their traditional use was as a powder that is mixed into warm wine or a decoction.

Chen Xiang is often not concentrated, due to its rarity and expense. Ge Jie is also very rarely seen as a concentrate because of its expense.

Xue jie and hu po are generally unable to be concentrated, and they are also traditionally taken as a powder.

Ru Xiang and Mo Yao are not very water-soluble, so they are sold as ground powders or concentrated by using alcohol as a solvent. Wine was traditionally used to dissolve these two products, so this practice is not too far from tradition.

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