Essential Oil Inhalation and Acute Stress Response in Healthy Adults

NCT07473544 | Active Not Recruiting DMC

• 1 other identifier: DO-126042-DMA
• Study Type: interventional
• Target: 200
• Locations: 1 country
• Sites: 1

Brief Summary

This randomized, double-blind, placebo-controlled study evaluates the acute physiological and subjective responses to essential oil inhalation in healthy adults. Participants are assigned to inhale either an essential oil or a placebo via an aroma stick during standardized laboratory procedures designed to induce temporary psychosocial stress (Trier Social Stress Test - Group version) and during a guided relaxation session. Physiological responses, including heart rate, heart rate variability, and electrodermal activity, are measured using a wearable sensor. Subjective stress and affect are assessed using validated questionnaires and visual analog scales. The purpose of this study is to characterize short-term autonomic and self-reported responses associated with essential oil inhalation under controlled experimental conditions. This study is exploratory and is not intended to diagnose, treat, or prevent any medical condition.

Conditions

Psychological Stress

Keywords

Stress; Aromatherapy; Essential Oils; Autonomic Nervous System; Stress Reactivity; acute stress; anxiety

Outcome Measures

Primary Outcomes (1)

• Change in Visual Analog Scale (VAS) Stress Area Under the Curve (AUC)

  Area under the curve (AUC) for self-reported stress measured using a Visual Analog Scale (VAS) across baseline, stress induction (Trier Social Stress Test - Group version), and post-stressor recovery periods. The VAS-stress scale ranges from low stress to high stress, with higher scores indicating greater perceived stress.

  Baseline through 30 minutes post-stressor recovery (Study Visit 1)

Other Outcomes (6)

• Change in Heart Rate During Stress and Recovery

  Baseline through 30 minutes post-stressor recovery (Study Visit 1), approximately 90 minutes from baseline

• Change in Electrodermal Activity During Stress and Recovery

  Baseline through 30 minutes post-stressor recovery (Study Visit 1), approximately 90 minutes from baseline.

• Change in PROMIS Anxiety Scores

  Baseline and post-stressor recovery (Study Visit 1), approximately 90 minutes from baseline.

Study Arms (2)

Essential Oil Inhalation

EXPERIMENTAL

Participants inhale an essential oil or essential oil blend via an individual aroma stick during standardized stress induction (TSST-G) and guided relaxation procedures across two study visits.

Other: Essential Oil Inhalation

Placebo Inhalation

PLACEBO COMPARATOR

Participants inhale a placebo aroma stick matched in appearance and delivery method but without active essential oil components during identical stress and relaxation procedures.

Other: Placebo Aroma Stick

Interventions

Essential Oil Inhalation OTHER

Participants inhale an essential oil or essential oil blend administered via an individual aroma stick. At prespecified time points during baseline, stress induction (Trier Social Stress Test - Group version), and recovery or guided meditation procedures, participants are instructed to take five normal breaths from the aroma stick. The intervention is delivered in a randomized, double-blind manner and is standardized across participants within each study phase.

Essential Oil Inhalation

Placebo Aroma Stick OTHER

Participants inhale a placebo comparator administered via an aroma stick identical in appearance and delivery method to the experimental intervention but without active essential oil components. The inhalation schedule and procedures are identical to those used in the experimental arm to maintain blinding.

Placebo Inhalation

Eligibility Criteria

• Age: 18 Years - 45 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64)

You may qualify if:

• Age 18-45 years, inclusive
• Able to read, write, and understand English
• Willing and able to provide informed consent
• Willing to attend two in-person study visits
• Generally healthy, as determined by medical history and screening review

You may not qualify if:

• Known asthma, chronic obstructive pulmonary disease (COPD), significant lung disease, heart disease, or other medical condition that may compromise safety or data integrity
• Pregnancy or pregnancy within the past 90 days
• Known allergy or sensitivity to essential oils or study placebo materials
• Current smoking, vaping, chewing tobacco, or use of recreational drugs
• Regular use of essential oils applicable to the study phase (\>3 times per week for ≥2 weeks within the past month) without a minimum 1-month washout
• Unwillingness to abstain from alcohol for at least 72 hours prior to each study visit

Sponsors & Collaborators

• dōTERRA International: lead

Study Sites (1)

dōTERRA International

Pleasant Grove, Utah, 84062, United States

Location

MeSH Terms

Conditions

Stress, Psychological; Anxiety Disorders

Condition Hierarchy (Ancestors)

Behavioral Symptoms; Behavior; Mental Disorders

Study Officials

• Nicole Stevens, PhD

  DoTERRA International LLC.

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: DOUBLE
• Who Masked: PARTICIPANT, INVESTIGATOR
• Purpose: SUPPORTIVE CARE
• Intervention Model: PARALLEL
• Sponsor Type: INDUSTRY
• Responsible Party: SPONSOR

Model Details: Participants are randomized in a 1:1 ratio to one of two parallel groups: essential oil inhalation or placebo inhalation. Randomization is maintained across two study visits. Participants remain in their assigned group for the duration of the study. An initial cohort of 100 participants (50 per arm) will be enrolled, with a prespecified interim analysis to determine whether enrollment will expand to a maximum of 200 participants.

Study Record Dates

• First Submitted: March 9, 2026
• First Posted: March 16, 2026
• Study Start: March 10, 2026
• Primary Completion (Estimated): March 1, 2027
• Study Completion (Estimated): December 31, 2027
• Last Updated: May 12, 2026

Record last verified: 2026-05

Locations

US (1)