According to Mosby's Medical Dictionary, the word 'rubefacient' derives from two Latin words: ruber, red, facere, to make, and it is defined as:

1. n, a substance or agent that increases the reddish coloration of the skin.
2. adj, increasing the reddish coloration of the skin.

This redness is caused by dilation of capillaries and increased blood circulation; a property that is useful for many client issues where pain or stiffness is present. An abstract published in Medline in 1982 reports the effects of a rubefacient commonly used by massage therapists and containing essential oils of cassia and clove called Tiger Balm. They tested application on rabbit skin to discover the effect of long term use and found that, "Tiger Balm Red (which contained 5% cassia oil plus 5% clove oil) caused irritation consisting of erythema, eschar formation and some oedema, to which a degree of tolerance developed. This irritation resulted in hyperkeratosis and sometimes inflammatory changes but no major damage to the skin. Tiger Balm White (no cassia oil and 2% clove oil) was better tolerated and produced less irritation and histological change than either Tiger Balm Red or a mixture of commercial waxes similar in composition to the wax base for Tiger Balm Red. None of the treatments produced any signs of systemic toxicity."

From this study, we learn two important things: rubefacients are well tolerated and don't cause permanent damage, and cassia oil is much more irritating than clove. Trained aromatherapists know this and also how important it is to dilute the rubefacient essential oils by putting them into carrier oil (such as almond, sesame, or my favorite, fractionated coconut) before use on the skin. And cassia (cinnamomum cassia) is listed in Sylla Sheppard Hanger's Aromatherapy Practitioner Manual, Vol. I as being a "DERMAL IRRITANT, avoid use on sensitive or damaged skin; use very highly diluted if at all."

There are many other essential oils that deliver the rubefacient property and which are more commonly used in massage application. They increase circulation in the skin and muscle tissue, creating relief from pain through an anti-inflammatory effect as well as helping to clear the tissue of byproducts of prior inflammation. They provide a comforting feeling of warmth as they accelerate metabolism in the area. Rubefacient essential oils are used to treat conditions such as rheumatoid and osteoarthritis, back pain, bunion, bursitis (application to area without massage or manipulation), muscle cramps, sciatica, strain and sprain. Frequently, they are paired with essential oils that increase detoxification, such as juniper berry (Juniperus communis), carrot seed (Daucus carota) and lemon* (Citrus limon). This is especially helpful for joint pain and arthritis. They can also be blended with more relaxing anti-inflammatory analgesics like lavender (Lavandula angustifolia, Lavandula spica) or German chamomile (Matricaria recutita) where stress and tension is known to be a major cause of muscle pain.

The commonly used rubefacient essential oils are:

• Black Pepper (Piper nigrum)
• Clove Bud (Eugenia caryophyllata)
• Eucalyptus (especially Eucalyptus radiata)
• Ginger (Zingiber officinale)
• Nutmeg (Myristica fragrans)
• Pine (Pinus sylvestris)
• Rosemary (Rosmarinus officinalis)

You can read profiles on some of those essences in an article on the stimulating essential oils published in the November 2011 issue of Massage Today. Nutmeg is less commonly used and has a reputation for having psychotropic properties. Studies have shown that this is true for whole nutmeg, while the essential oil is weak in the myristicin and elimicin content that metabolize to produce hallucinogenic effects. It is unlikely that non-oral use of the essential oil of nutmeg (the only safe method for delivering this and most essential oils) would have any such affects at all.

An example of a blend for chronic arthritis might be (in 1 oz of carrier oil):

An example of a blend for neck and/or back pain due to tension (in 1 oz of carrier oil):

Blending tip: Essential oils of higher aroma intensity require fewer drops.

*Expressed lemon essential oil is phototoxic. Avoid exposure to sunlight for 18 hours after use, or use distilled lemon essential oil.

References

1. Tisserand R, Balacs T. Essential oil safety. Churchill Livingstone, UK, 1995.

Shellie Enteen resides in Greer, S.C., and can be reached at shellie@astralessence.com. Shellie will be teaching a three day aromatherapy CEU workshop at the AMTA South Carolina Chapter Spring Mini-Convention in Charleston, SC, March 16-18th, 2012. More more information, visit www.amta-sc.org. For a brief biography, a printable version of this article and a link to previous articles, visit Shellie's columnist page at www.massagetoday.com/columnists/enteen.