Farnesol is a 15-carbon organic compound that can be classified as an acyclic sesquiterpene alcohol. It is produced from 5-carbon isoprene compounds in both plants and animals. Farnesol is present in many essential oils, including citronella, neroli, cyclamen, lemon grass, tuberose, rose, musk, balsam, and tolu. It has a delicate, sweet odor and is used in perfumery to emphasize the odors of sweet floral perfumes. Its mechanism of action for enhancing perfume scent is as a co-solvent that regulates the volatility of the odorants.

In cosmetics and personal care products, farnesol primarily functions as a fragrance ingredient. It can also be used as a deodorant because of its antibacterial activity. It has specific antimicrobial activity against gram-positive bacteria responsible for body odor. Farnesol is also classified as a “preservative booster” for its ability to increase the effectiveness of other preservatives in a formulation. Some claim that is can be used as an anti-aging ingredient because of antioxidant properties, however, there is no research showing that farnesol has any benefit on skin in this manner.