Autonomic and emotional responses after transdermal absorption of sweet orange oil in humans: Placebo controlled trial

Abstract

Essential oils are used increasingly for the improvement in quality of life and relief of various symptoms in patients, but scientific validation is still rare. The aim of this study was to investigate the effect of sweet orange oil (Citrus sinensis, Rutaceae) on human autonomic parameters and emotional responses in healthy subjects after transdermal absorption. In order to exclude any olfactory stimulation, the inhalation of the fragrances was prevented by breathing masks. Thirty nine healthy volunteers participated in the experiments. Four autonomic parameters, i.e. blood pressure, breathing rate, pulse rate and skin temperature were recorded. Emotional responses were assessed by means of rating scales. Compared to placebo, sweet orange oil caused significant decreases of breathing rate and pulse rate which indicate a decrease of autonomic arousal. At the emotional level, subjects in the sweet orange oil group rated themselves more cheerful and more vigorous than subjects in the control group. This finding suggests an increase of arousal in terms of self-evaluation. © Essential Oil Resource Consultants. All rights reserved.