Therapeutic agents are compounds with a beneficial and desirable effect when consumed or applied. These include a range of products, from topical aloe vera to soothe skin irritation to chemotherapy medications used to attack cancers. For safety reasons, many nations regulate them and set standards for purity and labeling. These laws protect consumers and provide guidelines for manufacturers to use in the development and marketing of their products.
http://www.wisegeek.com/what-are-therapeutic-agents.htm



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Note added at 14 minutes (2017-01-17 12:35:52 GMT)
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Всъщност agent е активно вещество, би трябвало product да свърши работа, но интересното е, че изплува предимно в сайтове от Нова Зеландия, Австралия и Сингапур.