Ointments have an extremely ancient history of being used as local applications for musculo-skeletal problems, but there is little sound data suggesting that the volume of essential oils, so absorbed, can have anything other than a localised effect. Many medical or physiological claims for essential oils are in fact caused by the act of massage itself. Diuretic action can be put down to massage rather than the action of specific oils. The increasing of blood circulation and manipulation of muscle groups is directly beneficial to relaxation and stress-relief without the use of any essential oils. Ordinary massage has been shown to produce a number of physiological effects on the body such as increase in Beta-endorphins which play a part in pain relief.
Many essential oils used by aromatherapists are inferior to the genuine article - often unknowingly.
Aromatherapy represents a tiny proportion of the international market in oils - the bulk of which goes to the food, pharmaceutical and fragrance industries. Essential oils often claim to be from 'small, independent suppliers', organically-grown in a particular country of origin. This is often a complete fabrication. They are produced in huge volumes for industries not in the slightest bit interested in aromatherapy. Their main concern is probably a pleasant smell in a bathroom cleaner - not the medical effect on the gall bladder.