Minireview : Effects of odors used in aromatherapy on blood pressure and autonomic nerve activity

Abstract

Aromatherapy is one of the popular complementary and alternative therapies used throughout the world. Several odors used as interventional stimuli in aromatherapy have been reported in previous studies to affect physiological indices. This minireview focuses on the effects of odor on blood pressure and autonomic nerve activity, as well as the mechanisms by which odor affects blood pressure and autonomic nerve activity. Odor inhalation is known to cause an increase or decrease in blood pressure. Furthermore, it has been reported that the blood pressure response to odor inhalation involves olfactory-central nerve system mechanisms, local vascular mechanism of action, and mechanisms mediated by afferent C fibers in the respiratory organ. It has also been found that there are differences in physiological responses induced by odor at different odor concentrations and the site of action, even though the odor type is the same. Therefore, medical aromatherapy is considered to be more effective when the odor type, odor concentration, and treatment method are appropriately selected according to the subject characteristics and purposes.