Feeling anxious before surgery or other medical procedures is common and understandable. Various complementary and alternative approaches, including aromatherapy, are being studied for reducing the need for medications to manage preoperative anxiety.
Animal studies have previously shown that some of the compounds found in eucalyptus - such as limonene and eucalyptol - may have anxiolytic properties. To test these benefits on humans, South Korean scientists investigated the effects of inhaling eucalyptus oil on anxiety levels in pre-surgical patients.
Carried out as a randomized, controlled clinical trial, it recruited 62 patients undergoing selective nerve root block (SNRB), an injection that helps diagnose and treat inflamed spinal nerves.
The patients were split into four groups, each with a different inhalation regimen:
- Group 1 inhaled 1% limonene dissolved in almond oil
- Group 2 inhaled 1% eucalyptol (also known as 1,8-cineole)
- Group 3 inhaled 1% eucalyptus oil
- Group 4 (the control group) inhaled almond oil
The oils were first applied to aroma pads, which patients were instructed to hold 30 centimeters (about 12 inches) from the tip of the nose and inhale the aroma for five minutes. After inhalations, they completed the required assessments, and 20 minutes later, they underwent SNRB.
Researchers used a variety of assessment tools (such as the anxiety-visual analog scale, or A-VAS, and the state-trait anxiety inventory, or STAI, among others) to measure the outcomes. They also recorded patients' changes in blood pressure and heart rate.
While anxiety levels decreased in all groups, the eucalyptol and eucalyptus oil groups showed a much greater decrease in all used assessments in comparison to other groups. Between the two, the eucalyptol group showed even better results.
Researchers contribute the overall decrease in anxiety levels across all groups to the emotional support and comfort patients have received from the staff.
Moreover, there were significant decreases in systemic blood pressure in the participants inhaling eucalyptol and eucalyptus. There were no significant changes in diastolic blood pressure or pulse.
What Does this Mean?
The results of this study demonstrate the anxiolytic effects of eucalyptus, particularly its major active component, eucalyptol.
Among many other therapeutic applications, inhalation of eucalyptol can be especially beneficial for reducing preoperative anxiety in patients undergoing surgery.
There are very important findings as studies have shown that higher anxiety levels may lead to poorer surgery outcomes.1 Using eucalyptus essential oil to calm the patients and reduce their stress levels has proven not only effective, but also free of side effects.
- Evidence-based Complementary and Alternative Medicine, The effect of 1,8-cineole inhalation on preoperative anxiety: a randomized clinical trial, 2014
- Scientific Reports. (2022). The effect of preoperative patient‑reported anxiety on morbidity and mortality outcomes in patients undergoing major general surgery. Retrieved February 9, 2023, from https://www.nature.com/articles/s41598-022-10302-z.pdf