Essential oils are a natural substance taken from plants. An essential oil is the concentrated liquid containing the volatile aroma compounds of the plant. Most oils are steam distilled from the flower or leaf. Essential oils are used in aromatherapy and natural skin care products.
Before using any essential oils, or a product that contains them make sure to do a patch test on a small area of skin before you use the product extensively. No matter what you read, NEVER ingest and essential oils. Be sure to never apply to eyes or other sensitive areas.
Neat Application of an essential oils means to use it undiluted on the skin. There are just a couple of oils in which this is safe to do. Lavender, is the one most commonly used neat. Under certain conditions, you can use Tea Tree, Sandalwood, and Ylang Ylang.
As with any natural substance, just because it is natural does not mean it is always safe to use. There are safety precautions when using essential oils. There are medical conditions, and health related instances where essential oils should not be used.
Those who have epilepsy should not use Camphor, Fennel (Sweet), Hyssop, Sage or Rosemary for any reason. Be sure to check any products you may be using for these ingredients.
Pregnant women should avoid most oils, but they especially should avoid using the following essential oils:: Ajowan, Angelica, Anise (Star), Aniseed, Basil, Bay Laurel, Calamintha (Catmint), Cedarwood (ALL types), Celery Seed, Cinnamon, Citronella, Clary Sage, Clove, Cumin, Cypress, Fennel (Sweet), Hyssop, Jasmine, Juniper, Labdanum, Lovage, Marjoram, Myrrh, Nutmeg, Origanum, Parsley, Peppermint, Rose, Rosemary, Sage, Snakeroot, Spanish Sage, Tarragon and Thyme. Many of them are considered emmenagogues. Emmenagogues are uterine stimulants and can cause a miscarriage.
Those who have high blood pressure, or have a tendency towards high blood pressure should avoid essential oils of rosemary, sage, thyme and hyssop. People who are diabeteic should stay clear of angelica.