Thujone, C₁₀H₁₆O, is the primary constituent of essential oils derived from a variety of plants, including wormwood, Artemisia absinthium; mugwort, Artemisia vulgaris; sage, Salvia officinalis; clary, Salvia sclarea; tansy, Tanacetum vulgare; and yellow cedar or the tree of life, Thuja occidentalis. While oils derived from the individual species may vary in the modifying constituents which they contain, the pharmacological effects common to thujone–containing plants are generally considered to include the following: 1 ) anthelmintic, 2) psychedelic, 3) uterine, 4) antidote to opium and other central nervous system depressant poisons. The effects delineated by modern experimentation correlate remarkably well with those ascribed to the plants in mythology, folklore, and other pre–contemporary documents.