In inhalation aromatherapy, the inhaled air containing essential oils can not only reach the circulation system via the blood capillary network in the nose and the bronchi in the lungs but also stimulate brain areas directly via the olfactory epithelium
Essential oils trigger mechanisms in the brain via the olfactory system. The mechanism of action of essential oils administered by inhalation involves stimulation of the olfactory receptors cells in the nasal epithelium, about 25 million cells, connected to the olfactory bulb.
After stimulation, the signal is transmitted to the limbic system and hypothalamus in the brain through the olfactory bulb and olfactory tract. Once the signals reach the olfactory cortex, release of neurotransmitters, for example, serotonin, takes place which results in the expected effect on emotions related to essential oil use.