Centaurea. Cnicus benedictus L. (Centaurea benedicta L.) Blessed Thistle. Chardon benit, Fr. Herba Cardui Benedicti, P. G. Benedicten Distel, G.—This is an annual herbaceous composite common in Europe and occasionally seen on roadsides and waste places in the United States. The leaves were formerly official. They should be gathered when the plant is in flower, quickly dried, and kept in a dry place. The herb has a feeble, unpleasant odor and an intensely bitter taste, more disagreeable in the fresh than in the dried plant.
Water and alcohol extract its virtues. The infusion with cold water is a grateful bitter; the decoction is nauseous, and offensive to the stomach. The active constituents are volatile oil and cnicin. This is crystallizable, inodorous, very bitter, neutral, scarcely soluble in cold water, more soluble in boiling water, and soluble in all proportions in alcohol. Its formula is C42H56O15, and it is analogous to salicin in composition. It has been used as a bitter tonic, and is, in larger quantities, emetic. Tonic dose, from half a drachm to one drachm (2.0-3.9 Gm.) preferably given as an infusion.
Silybum Marianum Gaertn. (Mariana Mariana, (L.) Hill, Carduus Marianus L.) was of old used for the same purpose as C. benedictus. Rademacher attributed great value to the seeds in hemorrhages, particularly when connected with diseased liver or spleen. Lobach found the decoction (two ounces to the pint of water), in doses of four fluidrachms (15 mils) every hour, useful in amenorrhea and menorrhagia. (Am. J. M. S., April, 1859.)