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Raindrop Therapy and the Use of Thyme & Oregano Essential Oils on the Skin


Question: In talking with a “Raindrop Technique” practitioner (Young Living Essential Oils), I learned that Thyme and Oregano Essential Oils are used neat (undiluted) on the skin during this technique. He has had only one experience which was reported negative, a person who suffers from candida experienced a “die-off’ reaction. He personally had done this technique 50 times with maybe 15-20 clients. Young Living is compiling testimonies from those involved with this technique and hope to publish the findings to further promote the use of Raindrop Therapy. I know you are a member of the National Association for Holistic Aromatherapy (NAHA) and I would like to know your opinion.

Answer: Thank you very much for sending the email about Young Living raindrop therapy. Since receiving your email I have taken some time to gather and reread National Association for Holistic Aromatherapy (NAHA) articles about essential oil safety. It is a big issue and I am more aware than ever before of specific safety aspects like sensitization, because of some of my own health issues. I used to disregard or ignore some safety cautions a long time ago and now I realize how very important these cautions are, especially to those individuals with histories of allergies, extra sensitive people or just those with chronic poor health.

Organizations like International Fragrance Research Association (link on our website) base their essential oil safety recommendations on an international panel of experts, made up of toxicologists, pharmacologists and dermatologists who have no commercial ties to the fragrance industry, and whose work involves the safety evaluation of fragrance materials under conditions of intended use. Their evaluations are based on existing data or, where insufficient data exist, on testing performed by RIFM itself. Besides the evaluations performed by the expert panel, an important step in maintaining credibility involves the publication of its findings and conclusions in a peer-reviewed and accredited scientific journal. They make very specific recommendations about how much of the more toxic essential oils should be diluted before applying to the skin. I personally have no faith in studies or surveys done by companies who sell the item being studied. I feel this way about any product and company, not just essential oils companies.

Here’s what the following authors say about Oregano  and Thyme oils:

Sheppard-Hanger, Sylla

The Aromatherapy Practitioner Reference Manual, Vol. 1, Vol. 2.

Tampa: Atlantic Institute of Aromatherapy. 1997.


Oregano Essential Oil Origanum vulgare L.

No formal testing; avoid in pregnancy, on babies, children; likely irritant; avoid on sensitive skin; hepato-toxic in large doses.


Thyme (Red Thymol) Essential Oil

Thymus vulgaris L.

Tested at low levels non-toxic (permitted food flavoring); highly irritant; non-sensitizing; not for use on damaged or sensitive skin; inhalations may be preferred over massage and bath; avoid with pregnancy, high blood pressure; hepato-toxic (?) in large amount and prolonged use.


Tisserand, Robert and Balacs, Tony

Essential Oil Safety.

Edinburgh: Churchill Livingstone. 1995.


Oregano Essential Oil Origanum vulgare L.

Hazards: moderate skin irritant, strong mucous membrane irritant. Cautions (dermal): Hypersensitive, diseased or damaged skin, children under 2 years of age. Cautions (inhalation, rectal, vaginal): Do not use at more than 1% concentration on mucous membrane. Toxicity data & recommendations: Undiluted oregano oil was severely irritating when applied to mouse skin and moderately irritating when applied to rabbit skin. Tested at 2% it produced no reaction after a patch test on human subjects. Comments: True oregano is Origanum vulgare, the herb used in the kitchen. However, the essential oil most commonly used in Europe is distilled from Thymus capitatus, and most safety data refer to this oil. Oils from many origins, as detailed above, may be offered as “oregano” or “origanum” oils.


Thyme (Red Thymol) Essential Oil Thymus vulgaris L.

Hazards: moderate? dermal irritant, strong mucous membrane irritant. Cautions (dermal): Hypersensitive, diseased or damaged skin, children under 2 years of age. Cautions (inhalation, rectal, vaginal): Do not use at more than 1% concentration on mucous membrane. Toxicity data & recommendations: Animal tests make thyme oil appear less toxic than would be expected from its content of thymol and carvacrol. Undiluted thyme oil was severely irritating to both mouse and rabbit skin; tested at 12% it produced no irritation on human subjects.


Schnaubelt, Kurt

Advanced Aromatherapy.

Rochester, Vermont: Healing Arts Press. 1998.


Oregano Essential Oil 

Origanum vulgare L.

Contraindications: not to be used on the skin…because its phenols can cause varying degrees of skin irritation, it recommends itself for internal use. Ideally oregano oil is taken in a carrier oil, such as sunflower. The amount of oregano oil should be about 50 milligrams (equivalent to 1-2 drops) per application…In general, use of oregano oil should be limited to treating acute conditions. The French aromamedical literature advises that the long-term use of this oil, or generally oils with a high phenol content, can lead to undesirable changes in the liver metabolism.


Thyme (Red Thymol) Essential Oil

Thymus vulgaris L.

Contraindications: not to be used on the skin…Note: This oil should not be applied externally.


Watt, Martin

Plant Aromatics.

Tampa, Florida: The Atlantic Institute of Aromatherapy. 1995.


Oregano Essential Oil  Origanum vulgare L.

A 2% solution of Origanum oil caused no irritation or sensitization on humans.


Thyme (Red Thymol) Essential Oil Thymus vulgaris L.

An 8% solution of Thyme oil (red unrectified) cased no irritation or sensitization on humans. Both Thyme oil and thymol have been recorded as being a cause of adverse dermal reactions including dermatitis, cheilitis and severe inflammation. Through personal experience and from unrecorded cases I have heard of, Thyme oil can be highly irritant on some people. In my opinion contact with the skin should be strictly limited to local treatments. The greatest care must be taken to avoid getting Thyme oil in the eyes and its use in baths should not be considered except for specific medical conditions under professional guidance. All chemotypes of thyme other than the thymol/carvacrol type should be treated as untested oils and appropriate precautions should be observed.

Neither one of these oils are considered sensitizers but I do think it is wise to seriously consider what these experts recommend for safe use. Just because something is safely used by one individual or by a company group surveyed, does not mean it will be safe for everyone in every situation. Companies promoting very bold use of essential oils contribute to members of the public assuming they can make up their own regimen of use and end up hurting themselves. I found an interesting but sad story in Salvatore Battaglia’s The Complete Guide to Aromatherapy. Included in his precautions about Eucalyptus essential oil he wrote “There is a reported incident where, for about the past five years, a man had been in the habit of swallowing five to ten drops of eucalyptus oil to keep colds at bay and to ‘make him feel good’. He began to feel discomfort and pain in the region of the liver. After entering hospital for a checkup, he was informed that he had been diagnosed with cirrhosis of the liver and that, unless he stopped drinking, his condition would further deteriorate. This man had never drunk alcohol. The apparent cause of his condition was the ingested eucalyptus which he had assumed would improve his health.”

I would be happy to mail you photocopies of all the safety articles published in the NAHA journals over the last few years. The best you can do is arm yourself with knowledge so you can make an educated decision about the essential oils and methods you choose.

Thanks for your email!

Response to answer: I appreciate your time and consideration. If its not too much trouble I would appreciate the documentation. More than anything I think the consumer owes it to himself to be “aware” particularly when dealing with an alternative medicine. I have taken a few courses in aromatherapy and do some work in the alternative medical field, mostly energy work and Bach Essences.

Occasionally I make an essential oil preparation for friends or myself, but as a former student of Anne Hall, I personally am very careful about PEO’s and carrier oils. IMO the whole of alternative medicine is harmed when a group of practitioners take it upon themselves to ignore safety precautions.

I have forwarded your note to the practitioner in question so HOPEFULLY it will open his eyes to the very real dangers of the raindrop therapy.

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