Teucrium: A plant genus of the family LAMIACEAE. Members contain teuscordonin. There have been reports of hepatoxicity by this genus.Scutellaria: A plant genus of the family LAMIACEAE used in folk medicine as a nervine.Achillea: A plant genus of the family ASTERACEAE that has long been used in folk medicine for treating wounds.Oils, Volatile: Oils which evaporate readily. The volatile oils occur in aromatic plants, to which they give odor and other characteristics. Most volatile oils consist of a mixture of two or more TERPENES or of a mixture of an eleoptene (the more volatile constituent of a volatile oil) with a stearopten (the more solid constituent). The synonym essential oils refers to the essence of a plant, as its perfume or scent, and not to its indispensability.Drug Contamination: The presence of organisms, or any foreign material that makes a drug preparation impure.