An Investigation of the Anxiolytic Effects of Aromatherapy in Mice

Abstract

Certain essential oils, in particular Lavender (Lavandula angustifolia), are claimed by proponents of aromatherapy to reduce anxiety, but there is limited scientific evidence for this. The purpose of this study was to determine whether essential Lavender oil has effects in animal models of anxiety. C57 mice were tested, an elevated plus maze, a common test of anxiety. Each mouse had two trials of five minutes in the maze, one with Lavender oil exposure prior to and during plus maze testing, and the other with exposure to distilled water. Another set of mice were tested in locomotor cages and in startle chambers where their acoustic startle response and prepulse inhibition of startle (PPI) was measured. Overall, mice spent more time and made more entries into closed arms of the elevated maze as expected. There was a tendency for Lavender oil exposure to decrease overall entries compared to water but there was no difference between the Lavender oil versus the water exposure in the percentage of time spent or the percentage of entries into the open arms. Lavender oil did not have any effect on acoustic startle response or PPI, but it did significantly decrease mobility in locomotor cages. These results suggest that Lavender oil does have bioactive, behavioral effects but that these effects are more consistent with non‐specific, sedation rather than anxiolytic‐specific effects.