Essential oils are powerful. While they are inherently much safer than prescription and over-the-counter medicines and few people are seriously injured by high quality oils, they do carry risks. They deserve respect as one of the most potent options available in natural medicine and require wisdom and education to use properly.
Avoid direct contact with eyes and the ear canal - if contact occurs, dilute with a carrier (fatty) oil like coconut, olive, or avocado.
Dilution - Opinions on essential oil use, including dilution, vary greatly. The specific essential oil and the reason for using it both factor into how it should be diluted; and the gentlest application that is effective is generally considered the wisest choice. Please consult reliable reference materials and/or professional advice for extensive usage guidance. Here are some very basic dilution suggestions to get you started:
1-3 drops of essential oil per tablespoon of carrier oil for the youngest, oldest and the most sensitive individuals
1-3 drops of essential oil per teaspoon of carrier oil for older children and most adults
Higher concentrations and neat (undiluted) application as needed and appropriate
Pregnancy - Opinions about which oils are contraindicated during pregnancy vary. Some oils that are recommended against during pregnancy include: fennel, calamus, tarragon, nutmeg, basil, rosemary, clary sage, hyssop, sage, and tansy. Some physicians will still prescribe these oils in small amounts if the patient tests positively for them. Some individuals will use these oils in blends (such as the rosemary in Thieves) in small to moderate amounts for acute situations and others avoid them and some others entirely. It is the responsibility of each family to decide for themselves what is best. Consulting with the maternity care provider of your choice about all supplements and natural medicines is recommended.
Nursing - Excessive use of peppermint essential oil can decrease milk supply. Different sources cite various oils to use with care or to avoid while nursing.
Babies/Young Children - Essential oils should always be used with special care on babies and young children, and diluting is the most conservative way to go about applying them topically. Some sources assert that using the oils rich in 1,8 Cineole on the bottoms of the feet of children is safe, but not around the throat or face or directly inhaled (diffusion is not the same as direct inhalation); others completely avoid using on or even around children under 10. Peppermint is generally used with more universal caution when it comes to the youngest children. Expert opinions on the use of peppermint oil vary, some saying that it is fine to use diluted on the soles of the feet after 18 months and some saying that it's better to wait until 3 years of age. Still others recommend 6 years.
Some will use these oils with less caution (topically or diffused) if they are in blends (such as RC) and some suggest the same precautions regardless of the preparation if an oil contains these chemical components.
Some sources feel perfectly comfortable using well-diluted gentle essential oils on babies and others prefer to utilize other options, such as floral waters.
Medical Conditions/Medications - There are various opinions on which essential oils should be contraindicated for those with certain conditions and using different medications, some being more conservative than others. It is always recommended that you work alongside the knowledgeable healthcare professionals of your choice as you make decisions about these matters. Many essential oil reference books have more information on this topic, including some specific contraindications.
Sun Exposure - Citrus essential oils can increase photosensitivity. Take care to protect skin on which citrus oils have been topically applied for at least 12 hours after application.
Internal use - Some sources discourage internal use except under the guidance of a professional and others find it reasonable for educated laypeople to administers oils orally as needed. The quality of essential oils is especially important when they are being used internally.
More - For more information and additional precautions from various perspectives, see the essential oil reference books listed under the Books tab, which is located in the Holistic Health Resources section. The Essential Oil Reference books by Life Science Publishing contain the latin names of essential oils, as well as the major chemical components like menthol and 1,8-Cineole.
**As is the case in every realm of natural and allopathic medicine, opinions on essential oil uses, precautions, and contraindications vary and even evolve over time. It is the responsibility of individuals/families to consult with the knowledgeable healthcare providers of their choice and to make informed decisions about what is best for themselves in regard to these issues.
There are many factors that contribute to the safety of essential oils, including the quality of the oil production methods and the manners of usage. While certain chemical constituents of essential oils carry universal precautions regardless of the quality of the oils, some concerns and precautions related to the use of adulterated or otherwise inferiorly produced essential oils are not necessarily relevant to very high quality oils when they are used with wisdom and common sense.
It is a wise general principle of natural medicine to use the most conservative/gentle option or application that produces the desired effects.**