Natural substances from the group of alkaloids, or according to latest discoveries from biogenic amines, such as theobromine, theophylline and caffeine are present all together in higher medicinal plants of the Old World as well as the New World. They influence the human organism as psychomotor stimulants. There are six genera of mother plants (the Coffee Tree, Tea Tree, Cola, Cocoa Tree, Holly and Empress Tree), with numerous species, hybrids and other taxa at the cultivar level. Various caffeine drugs are still used as therapeutics, but they are no longer used as strategic pharmaceuticals.
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