|Guidelines for Using Essential Oils and Herbs|
Because essential oils are concentrated, highly potent substances, a working knowledge of how to use them safely is vital to the success of your efforts. The potential hazards of an essential oil depend on the compounds in the oil, the dosage and frequency used, and the method of application. Here are a few guidelines to ensure safe and effective use of essential oils:
Don't use undiluted essential oils on the skin. They can cause burning, skin irritation and photosensitivity. There are a few exceptions to this rule: it is acceptable to use the nonirritating oils lavender or tea tree undiluted on burns, insect bites, pimples and other skin eruptions-as long as you don't have extremely sensitive skin. If you find an essential oil irritating but would like to use it, and have determined that the irritation is not due to an allergy, try massaging the diluted blend into the soles of your feet. The oil will not irritate the skin, and will still enter the body.
Use only pure essential oils from plants.
Test for sensitivities. Most people with sensitivities to synthetic fragrances are not sensitive to high-quality essential oils. Also people who are allergic to, say, chamomile tea will not necessarily be allergic to the essential oil. If you are uncertain about an oil, do a patch test of a 2-percent dilution in the crook of the arm or on the back of the neck at the hairline. Twelve hours is ample time for a reaction to occur. If redness or itching develops, you may want to try a less potent dilution, or choose an appropriate substitute for the irritating oil.
Use with caution those essential oils that result in photosensitivity. Citrus oils can irritate skin, and some of them will cause uneven pigmentation of the skin upon exposure to sun lamps or sunlight. This is especially true of bergamot, which contains bergaptene, a powerful photosensitizer that will cause allergic reactions in some individuals. (Bergaptene-free oil is available.) Of the citrus oils, bergamot is the most photosensitizing, followed by cold-pressed lime, bitter orange, and to some degree, lemon and grapefruit. Of the lemon oils, California oil is the least photosensitizing. If you are using photosensitizing oils on your skin, do so at night, stay indoors, or wait at least four hours before exposing your skin to ultraviolet light.
Use with caution those essential oils that are irritating to mucous membrane (the lining of the digestive, respiratory and genito-urinary tracts) and skin. Keep all essential oils away from the eyes.
Keep all essential oils out of the reach of young children; older children can be taught to respect and properly use essential oils, but they should nevertheless be supervised. In general, when treating children with essential oils use one-third to one-half the adult dosage and select only nontoxic oils. Among the best and safest essential oils for children are lavender, tangerine, mandarin, neroli, frankincense, petitgrain and Roman chamomile.
Vary the essential oils you use. Using the same facial oil blend for a long period of time is acceptable because it covers a very small part of the body, but daily application of the same blend of oils over your entire body for more than two weeks is not recommended. It is wise to alternate with a blend of different oils containing different chemical constituents at least every two weeks. Uninterrupted use of some oils exposes your liver and kidneys to chemical constituents that may be harmful over time. Rotating the oils gives your body time to process them and allows each oil to work on different levels in its own unique way.
Don't take essential oils orally for therapeutic purposes. Safe ingestion of oils requires a great deal of training and is therefore not recommended for beginners. The exception is when we suggest using essential oils to flavor foods (see Chapter 10: Essential Oils in the Kitchen). The dosages per serving in these recipes are minimal and harmless.
Use essential oils cautiously with those who are elderly, convalescing, or have serious health problems such as asthma, epilepsy or heart disease.
Be cautious about using essential oils during pregnancy, especially during the first trimester. Even oils that are generally safe during this time may be too stimulating for women who are prone to miscarriage. Because so many oils are best avoided in pregnancy, it is easier to list the safe ones: gentle floral oils such as rose, neroli, lavender, ylang-ylang, chamomile and jasmine absolute, as well as the citruses, geranium, sandalwood, spearmint and frankincense.
Overexposure to an essential oil, either through the skin or through inhalation, may result in nausea, headache, skin irritation, emotional unease or a "spaced-out" feeling. Getting some fresh air will help overcome these symptoms. If you ever experience skin irritation or accidentally get essential oils in the eyes, dilute with straight vegetable oil, not water.
The following information is adapted from The Essential Oil Safety Data Manual by Robert Tisserand. We recommend this book to anyone interested in a thorough study of toxic oils.
Potentially Toxic Oils
Some of the oils in the following list have limited use externally; others are used for perfumery. We have included Latin names to avoid any confusion.
|Photosensitizing Essential Oils|
|clove||thyme (except linalol)|
|dwarf pine||thyme (except linalol)|
almond, bitter (Prunus amygdalus var. amara)|
inula (Inula graveolens)
khella (Ammi visnaga)
mugwort (Artemesia vulgaris)
pennyroyal (Mentha pelugium)
sassafras (Sassafras albidum)
thuja (Thuja occidentalis)
wintergreen (Gaultheria procumbens)
Very Toxic Essential Oils
We recommend not using the following oils at all.
ajowan (Ptychotis ajowan, Carum ajowan)|
arnica (Arnica montana)
boldo (Peumus boldus)
buchu (Barosma betulina)
calamus (Acorus calamus)
cascarilla (Croton eluteria)
chervil (Anthriscus cerefolium)
camphor, brown and yellow (Cinnamomun camphora)
deer tongue (Carphephorus odoratissimus)
horseradish (Cochlearia armoracia, Armoracia rusticana)
jaborandi (Pilocarpus jaborandi)
mustard (Brassica nigra)
narcissus (Narcissus poeticus)
nutmeg (Myristica fragrans)
parsley (Petroselinum sativum, Carum sativum)
rue (Ruta graveolens)
santolina (Santolina chamaecyparissus)
Spanish broom (Spartium junceum)
tansy (Tanacetum vulgare)
tonka (Dipteryx odorata)
turmeric (Curcuma longa)
wormseed (Chenopodium ambrosioides, C. anthelminticum)
wormwood (Artemisia absinthium)
Methods of Application
The most effective way to dilute essential oils is in a carrier oil. A carrier can be any high-quality vegetable oil, such as almond, apricot, hazelnut, olive, grapeseed or sesame.
A safe and effective dilution for most aromatherapy applications is 2 percent, which translates to 2 drops of essential oil per 100 drops of carrier oil. There is no need to go beyond a 3-percent dilution for any purpose. In aromatherapy, more is not better; in fact, "more" may cause adverse reactions. Some oils, such as lavender, are sedating in low dilutions and stimulating in high dilutions. A 1-percent dilution should be used on children, pregnant women, the elderly and those with health concerns.
You can create a safe and effective remedy with just one, two or three oils. When combining essential oils in a therapeutic blend, it is best for beginners to keep it simple, using no more than five oils at a time. Using more than five may lead to unpredictable results because of the complex chemistry created by the combination of all the oils.
|1% dilution:||5-6 drops essential oil per ounce of carrier oil|
|2% dilution:||10-12 drops essential oil per ounce of carrier oil|
|3% dilution:||15-18 drops essential oil per ounce of carrier oil|
We are often asked, "How big is a drop?" This is a very good question, because the size of a drop varies depending on the size of the dropper opening, as well as on the temperature and the viscosity (thickness) of the essential oil. A drugstore dropper will probably be accurate enough for your purposes.
Some people find it easier to use drops; others prefer measuring their essential oils by the teaspoon. Teaspoons are usually more convenient when preparing large quantities. Whatever your preference, use the chart on the following page as a general guideline. We've rounded off the measurements for your convenience. The ratios of drops to teaspoon were calculated using water, which has a medium viscosity compared with the range of viscosities found in essential oils.
Storage and Shelf Life
Store essential oils away from heat and light to preserve their freshness and potency. When stored properly, they have a shelf life of several years. The citrus oils have the shortest shelf life of all essential oils and are best used within one year. The longest-lasting oils, which improve as they age, tend to be the thick resins such as frankincense and myrrh, woods such as sandalwood, roots like vetiver, as well as other oils, including spikenard and patchouli.
|Measurement Conversion Chart|
|10 drops||1/10 tsp.||1/96 oz.||1/8 dram||about 1 ml.|
|12.5 drops||1/8 tsp.||1/48 oz.||1/6 dram||about 5/8 ml.|
|25 drops||1/4 tsp.||1/24 oz.||1/3 dram||about 1 1/4 ml.|
|50 drops||1/2 tsp.||1/12 oz.||2/3 dram||about 2 1/2 ml.|
|100 drops||1 tsp.||1/6 oz.||1 1/3 drams||about 5 ml.|
|150 drops||1 1/2 tsp.||1/4 oz.||2 drams||about 13.5 ml|
|300 drops||3 tsp.||1/2 oz.||4 drams||about 15 ml.|
|600 drops||6 tsp.||1 oz.||8 drams||about 30 ml.|
|24 teaspoons||(8 tablespoons)||4 oz.||1/2 cup|
|48 teaspoons||(16 tablespoons)||8 oz.||1 cup||1/2 pint|
|96 teaspoons||(32 tablespoons)||16 oz.||2 cups||1 pint|
About The Author
has studied herbs since 1969. Her attraction to fragrant plants led to an involvement in aromatherapy. Her other books include Herbs for Health and Healing
; The Illustrated Encyclopedia of Herbs
; and Herbs: American Country Living
. Keville is editor of the American Herb Association Quarterly
, an honorary life member of the American......more