In Europe, where the Centaurium erythraea is indigenous, dried centaury herb is made into a decoction or tea and drunk as a "tonic." 

Rolf Stühmer, German-born author of Das Große Buch der Naturheilkunde ("The Big Book of Health," first published in 1997 by the University of Potsdam Press) believes that every good store of herbs should include organic centaury herb.