OVERVIEW.

Aromatherapy is the application of essential aromatic plant oils (highly concentrated, pure extract), applied internally or externally to address health problems. Essential oils are plant or tree products (i.e., leaves, berries, bark, roots) derived from one species using a physical process (e.g., distillation). In its external application, aromatherapy incorporates the use of essential oils with massage to address tension headaches, treat depression, or induce a sedative effect.^1,2

Precautions or advice below is generally based on concerns for adverse reactions leading to toxicity, skin and mucous membrane irritation, sensitization (allergies), photosensitization, or for use in specified populations (pregnancy, epilepsy, hypertensive or hypotensive conditions).¹ Other concerns relate to some novel (not adequately tested) and potentially toxic essential oils and herbal oils (i.e., phytols or infused oils) used in aromatherapy.²

Note: In 1999, Burkhard et al³ reported two adults who exhibited generalized tonic-clonic seizures and one child who suffered a generalized tonic status seizure, all associated with the absorption of oils (several) for therapeutic purposes. These plant-related toxic seizures were attributed to highly reactive monoterpene ketones such as camphor or thujone contained in the oils. In 1981, Millet et al⁴ reported eight cases of human intoxication (tonic-clonic convulsions) with sage, hyssop, thuja, and cedar. These researchers also demonstrated the convulsive-related toxic properties of commercialized sage and hyssop essential oils in rats using electrocortical recordings.