There are two different types of sprays. The first type is tannic acid-based (Allersearch ADS Anti-allergen Spray). Tannic acid is found in the bark of trees, the leaves of tea, and the peels of grapes. It is a very powerful denaturing agent.
Another type of allergy control spray does not depend on tannic acid as the active ingredient (Allerserach ADMS Anti-allergen Spray). These sprays use a combination of other acids, alkalis, and enzymes to neutralize proteins. They denature in much the same way as tannic acid. However, because tannic acid is not present you do not run the risk of staining or discoloration.
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