The study of where essential oils go when they are absorbed and how they are absorbed and eliminated by the body is called pharmacokinetics. Essential oils are absorbed into the body through digestion, through the “internal skin” lining of orifices, by olfaction, and through the external skin.
There is fairly heated debate as to how aromatherapy should be used. Some people believe the term aromatherapy means just that: inhalation. But, in many parts of the world, aromatherapy is often combined with touch, as the absorption of essential oils through the skin coupled with soothing touch (or warmth) may enhance and prolong their therapeutic effects. Some believe the sublingual, rectal, and vaginal routes of absorption are the most effective. Others believe essential oils are most useful when taken orally and digested. Clearly there is a difference in metabolism between a substance that is ingested and one that is applied topically (to internal or external skin) or inhaled. Ingestion of essential oils is more akin to Western medicine.
There are four methods by which the components within essential oils can be absorbed.
- Topical: using external skin via touch, compress, or bath
- Internal: using internal skin via mouthwashes
- Oral: via gelatin capsules or diluted in honey, alcohol, or a dispersant (purchasable from most good essential-oil companies)
- Inhaled: directly or indirectly, with or without steam.