Eucalyptol

Definition: Eucalyptol, also called 1,8-cineole, is a terpene with a cool, minty, camphor-like smell. It’s the main compound in eucalyptus oil and also occurs in rosemary, bay leaves, and sage. In cannabis, eucalyptol is usually a minor terpene, present in small amounts that add a fresh, cooling note to some strains.

What Is Eucalyptol?

Eucalyptol is a monoterpenoid, a modified terpene with the formula C10H18O. It’s widely used in mouthwashes, cough drops, chest rubs, and fragrances because of its strong cooling aroma.

What Does Eucalyptol Smell Like?

Think of a eucalyptus steam room or a menthol cough drop: sharp, minty, and clean, with a camphor edge. Even in small amounts, it can make a strain smell noticeably fresher.

What Are the Effects of Eucalyptol?

Eucalyptol has better human research than most terpenes, though not in the context of cannabis. In a 2003 double-blind, placebo-controlled trial published in Respiratory Medicine, people with severe asthma who took oral 1,8-cineole were able to cut their steroid doses more than those on placebo. Lab and animal research also points to anti-inflammatory and antimicrobial activity. Whether the small amounts in cannabis have any noticeable effect is unknown.

Where Is Eucalyptol Found?

Eucalyptus leaves are the richest source. Eucalyptol also shows up in rosemary, bay leaves, sage, basil, cardamom, tea tree, and wormwood.

Related terms: Terpenes, Pinene, Nerolidol, Entourage Effect

Sources: Juergens UR et al., “Anti-inflammatory activity of 1.8-cineol (eucalyptol) in bronchial asthma: a double-blind placebo-controlled trial,” Respiratory Medicine, 2003; PubChem: Eucalyptol.