umbellulone

Umbellulone is a **monoterpene ketone** and the major bioactive constituent of the leaves of *Umbellularia californica* (California bay laurel), sometimes known as the "headache tree"[3][5][6][11]. It is a lipophilic, bicyclic ketone (C10H14O, MW 150.22) that acts as an irritant and is best known for inducing headache and cluster headache in susceptible individuals due to its pronounced effects on the trigeminovascular system[3][5][11]. Its mechanism involves potent activation of the **transient receptor potential ankyrin 1 (TRPA1) channel** on nociceptive peptidergic neurons, resulting in calcium influx, CGRP (calcitonin gene-related peptide) release, meningeal vasodilation, and inflammatory signaling associated with headache and migraine [3][5][7][11]. Umbellulone can also activate TRPM8 weakly, causing cold sensation, but its major action is TRPA1 agonism [3]. It is not approved as a pharmaceutical product for any indication and is primarily used in research to study pain, migraine mechanisms, and trigeminal system activation[5][6][7][11]. There are no known developers or approved formulations of umbellulone for medicinal use.

Other names

Umbellulon3-Thujen-2-oneTHUJEN-2-ONETHUJEN2-ONETHUJEN 2-ONE4-methyl-1-propan-2-ylbicyclo[3.1.0]hex-3-en-2-oneThujenone546-78-124545-81-1