Sage oil is the essential oil

Essential oil

An essential oil is a concentrated hydrophobic liquid containing volatile aroma compounds from plants. Essential oils are also known as volatile oils, ethereal oils or aetherolea, or simply as the "oil of" the plant from which they were extracted, such as oil of clove...

 made from the culinary herb sage

Common sage

Salvia officinalis is a small, perennial, evergreen subshrub, with woody stems, grayish leaves, and blue to purplish flowers. It is a member of the family Lamiaceae and is native to the Mediterranean region, though it has naturalized in many places throughout the world...

, Salvia officinalis. In addition to its valuable flavoring characteristics, sage oil can contain as much as 50% thujone

Thujone

Thujone is a ketone and a monoterpene that occurs naturally in two diastereomeric forms: -α-thujone and -β-thujone. It has a menthol odor. Even though it is best known as a chemical compound in the spirit absinthe, recent tests show absinthe contains only small quantities of thujone, and may or may...

 by weight. The exact amount varies based on the time in the season and which part of the plant is tested. Thujone is traditionally regarded as one of the active ingredients in absinthe

Absinthe

Absinthe is historically described as a distilled, highly alcoholic beverage. It is an anise-flavoured spirit derived from herbs, including the flowers and leaves of the herb Artemisia absinthium, commonly referred to as "grande wormwood", together with green anise and sweet fennel...

, distinguishing it from "less controversial" alcoholic beverages.

Sage oil has been suggested to boost short-term memory performance in many using it as a dietary supplement. Sage oils can be toxic and may trigger miscarriages, as well as "cause dizziness, rapid heartbeat, and provoke epileptic seizures".