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Page 46
pecially with echinacea, is that they lose their potency relatively quickly. Powdered echinacea can lose some of its effectiveness in as little as four months. Echinacoside content can degrade 10 percent in three years.36 Capsules lose their potency the quickest because a relatively high amount of surface area is exposed to light and air, which causes the active constituents to oxidize. Tablets can retain their potency for relatively long periods of time as they are tightly packed and therefore little surface area is exposed to oxidation. One potential disadvantage to both capsules and tablets is that the majority of these products also contain some amount of excipients and flow agents. The most commonly used excipients include di-calcium phosphate and magnesium stearate, both of which are considered basically inert. Depending on the manufacturer, excipients can account for less than 5 percent to higher than 35 percent of the total weight of the capsule or tablet. If improper tableting techniques are used, they can be too hard and therefore will not dissolve adequately. How well tablets dissolve can be tested by placing a few tablets in a cup of cold water. If they dissolve within 30 to 60 minutes in the passive medium of a plain cup of water, you can be assured they will quickly break down in the active medium of the digestive system.
Liquid Extracts
Alcohol: Alcohol extracts are by far the most commonly used echinacea preparations on the market. They have the advantage of coming in small one-fluid-ounce eyedropper bottles and so are very easy to carry. If extracted properly, they will capture a large percentage of the medicine contained within the

 
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