Plant species include Matricaria recutita, Chamomilla recutita, and Matricaria chamomilla. Chamomile tea, brewed from dried flower heads, has been used traditionally for medicinal purposes. The main constituents of the flowers include phenolic compounds, primarily the flavonoids apigenin, quercetin, patuletin, luteolin, and their glucosides. The principal components of the essential oil extracted from the flowers are the terpenoids a-bisabolol and its oxides and azulenes, including chamazulene. Chamomile has moderate antioxidant and antimicrobial activities, and significant anti-platelet activity in vitro. Animal model studies indicate it may have potent anti-inflammatory action, some antimutagenic and cholesterol-lowering activities, as well as antispasmotic and anxiolytic effects. However, human studies are limited, and clinical trials examining the purported sedative properties of chamomile tea are absent. Adverse reactions to chamomile, consumed as a tisane or applied topically, have been reported among those with allergies to other plants in the daisy family (Sources: Phytotherapy Research, July 2006, pages 519–618; www.herbmed.org; European Journal of Drug Metabolism and Pharmacokinetics, October–December 1999, pages 303–308; and Planta Medica, October 1994, pages 410–413).