Essential oils are renowned for their immune-supporting and emotion-balancing qualities. When used safely, Aromatherapy is a simple and delightful way to support health and “Well BEEing”.

Credit is due to Robert Tisserand and Rodney Young’s book, Essential Oil Safety: A Guide for Health Care Professionals (second edition) and The Aromahead Institute for keeping safety at the forefront of their curriculum. 

To ensure the safe use of essential oils, it is crucial to consider the following precautions

Pregnancy and Breastfeeding:

• Essential oils should be used cautiously during these times, with a recommended concentration of 1%. Pregnant women are advised to seek guidance from an Aromatherapist or medical professional knowledgeable about essential oils.

• Approximately 50 essential oils are contraindicated during pregnancy, and another 15 should be restricted during pregnancy and lactation. These are some of the most commonly used oils that are contraindicated during pregnancy: Anise, Birch, Black Seed, Carrot Seed, Cinnamon bark, Blue Cypress (Callitris intratropica), Fennel, Ho leaf (Cinnamomum camphora ct. camphor), Hyssop (Hyssopus officinalis ct. pinocamphone), Myrrh, Spanish Lavender (Lavandula stoechas), Oregano, Sage (Salvia officinalis, Salvia lavandulifolia) and Wintergreen.

Convulsant Risk:

• Certain essential oils are potentially convulsant for individuals vulnerable to epileptic seizures. Western Red Cedar, Wormwood, Genipi, Hyssop (ct pinocamphone), Sage, Thuja, Pennyroyal, Buchu, Calamint, Tansy (Tanacetum vulgare), Mugwort, Lanyana, Ho Leaf (ct camphor), Boldo, Wintergreen, Birch, Rosemary, Yarrow, Spanish Lavender (Lavandula stoechas), Feverfew, and Spike Lavender (Lavandula latifolia). Tisserand and Young's book (p.134, table 10.2).

High Blood Pressure:

• There is no evidence supporting the contraindication of topical use of essential oils for high blood pressure. Diluting essential oils in carrier oils is recommended, with a general guideline of 5–18 drops of essential oil in 1 oz (30 ml) of carrier oil.

Age Considerations:

• For children aged 5–12, elders on multiple medications, pregnant women, and those with serious health conditions, starting with a low concentration of 1% is advisable. The use of oils for babies and young children should be approached with caution, favoring alternatives like hydrosols, aloe vera gel, butters, and carrier oils for topical application.

Phototoxicity:

• Certain oils, such as Bergamot, Lemon, and Grapefruit, can cause phototoxic reactions. Sunlight or tanning bed exposure should be avoided for up to 18 hours after application if these oils are used above specified levels.

Safety Precautions:

• Essential oils should not be applied directly to the eyes, ears, or other orifices. If contact with the eyes occurs, wash hands with soap and water, apply carrier oil to a paper towel, and gently wipe the eye. People with asthma, allergies, or multiple chemical sensitivities should proceed cautiously with essential oils.

Cancer Treatment:

• Essential oils should be avoided from one week before to one month following chemotherapy or radiotherapy due to potential effects on immune mechanisms.

General Safety:

• Keep essential oils out of the reach of children, as they can be poisonous if swallowed. Internal use of essential oils is only recommended under the guidance of a trained clinical Aromatherapist with expertise in pharmacodynamics, pharmacokinetics, formulation techniques, and safety issues related to each route of application.

By adhering to these precautions, one can fully enjoy the benefits of aromatherapy while prioritizing safety and well-being.

Allergic Reactions to Essential Oils (hopkinsmedicine.org):

A small number of people may experience irritation or allergic reactions to certian essential oils. You’re more likely to have a bad reaction if you have atopic dermatitis or a history of reactions to topical products. Although you can experience a reaction to any esential oil, some are more liekly to be problematic, including: Oregano oil, Cinnamon bark oil, Jasmine oil, Lemongrass oil, Ylang-ylang oil, Chamomile oil, and Bergamot oil. Because pure essential oils are potent, diluting them in a carrier oil is the best way to avoid a bad reaction when applying directly to the skin.

Many essential oils are available as hydrosols, enabling a person to receive the therapeutic benefits of a given chemotype without the potential of a reaction to potency. Hydrosols are also safe to use on children and pets.

Potential Drug Interactions (the short list) with Essential Oils:

Directly from The Aromahead Institute:

1. Oral Route: Use caution with Peppermint oil and calcium channel antagonists. Peppermint oil is a calcium channel blocker and may alter the effects of these drugs (specifically felodipine was mentioned in the research). Calcium channel blockers are common medications given for high blood pressure. In this instance, Peppermint may potentiate the medication. Oral use of Peppermint should also be avoided in case of gastro esophageal reflux disease (GERD). Mentholrich oils should also be avoided by anyone that has been advised to avoid antimalarials, sulfonamides, chloramphenicol, streptomycin or aspirin.

2. Any Route: Caution is advised when using sedating oils with anyone receiving barbiturates, benzodiazepines or anesthetics, due to possible interaction with the drugs.

3. Any Route: Oils containing methyl salicylate (Birch, Wintergreen) should be avoided with anticoagulant drugs (blood thinners) such as Warfarin, Coumadin, Aspirin or Heparin. Methyl salicylate is known to inhibit blood coagulation and may potentiate the effects of the drugs, causing internal hemorrhage. Even small doses applied topically can cause problems and should be avoided by people with clotting disorders, major surgery, childbirth, peptic ulcer or hemophilia.

4. Any Route: People who have aspirin sensitivity should not use oils containing methyl salicylate (Birch, Wintergreen). Methyl salicylate is converted into salicylic acid in the body. This is an example of an essential oil component being the same as the concentrated ingredient of the drug. Salicylate sensitivity applies to most children with ADD/ADHD.

5. Oral Route: All oils containing eugenol (Clove), thymol (Thyme ct. thymol) and carvacrol (Oregano) should be avoided by people taking anticoagulant medication, with clotting or bleeding disorders, major surgery, childbirth, peptic ulcer or hemophilia. These components “thin” the blood and could cause excessive bleeding.

6. Oral Route: Eugenol (Clove) may interact with MAOI or SSRI drugs which are found in antidepressants. Oral doses of oils containing eugenol (Clove) or myristicin (Nutmeg) should not be taken with antidepressants due to possible blood pressure changes, tremors or confusion. It is also inadvisable to take alongside ephedrine as potentially dangerous cardiovascular changes may occur.

7. Topical Route: If drugs are being given transdermally (through a skin patch), essential oils must not be applied to the area of the drug patch, or in the close vicinity. This helps avoid possible alterations in the drug’s bioavailability. The essential oils could speed up or slowdown the delivery of the drug, thus altering the assumed dose.

8. Any Route: If there is significant hepatic (liver) and renal (kidney) impairment the person will be more vulnerable to the potential toxic effects of the oils with overuse. Intensive or internal use of the oils must be avoided, as the liver is used to metabolize/detoxify, and kidney to excrete the essential oils.

9. Any Route: Eugenol, thymol and carvacrol (Clove, Thyme ct. thymol, West Indian Bay Oil) are potent prostaglandin inhibitors, and are to be avoided by people with significant renal (kidney) disease. This is because drug treatment for renal disease increases renal blood flow by mechanisms that are dependent on the effects of prostaglandins.

10. Any Route: Oils containing farnesene and alphabisabolol (Balsam Poplar, German Chamomile, Blue Tansy, Yarrow) inhibit some metabolizing enzymes (CYP2D6) and could potentiate the actions of some antidepressants such as quinidine, fluoxetine and paroxetine.

These oils used topically or orally could also have drug interaction with codeine and tamoxifen.

Tisserand states that the risk is considered "theoretical" based on the research.

11. Oral Route: Oils containing citral (Lemongrass, May Chang, Honey Myrtle, Lemon Myrtle) should not be used orally with antidiabetic medication.

12. Any Route: Oils containing citral (Lemongrass, May Chang, Honey Myrtle, Lemon Myrtle) should also be avoided with antidepressants (specifically Bupropion) that inhibits CYP2B6 enzyme, as the oils could potentiate drug action. Tisserand states that the risk is considered "theoretical" based on the research.