Thoughts on Tea Tree Oil

Let me start this post by saying I don't recommend, endorse, or even use any special lice shampoos or treatments.  If you've read this blog before, you know this.  However, you also know I'll let you know about lice research.  And one of the questions I get asked about most is tea tree oil. 

For years, I've looked, but never found any strong research on tea tree oil in relation to head lice.  But today I found the synopsis of a 2010 study done at the University of Queensland.    Follow the link to see the abstract. The catchy title says it all: "A randomised, assessor blind, parallel group comparative efficacy trial of three products for the treatment of head lice in children--melaleuca oil and lavender oil, pyrethrins and piperonyl butoxide, and a "suffocation" product."

This study seems to demonstrate that a shampoo with tea tree oil AND lavender oil has effectiveness against head lice.  Before you go out and buy a bunch of essential oils, please consider these points:

1. Just because something is seen as "natural", it doesn't guarantee safety.
The American National Institutes of Health offers these cautions about tea tree oil:
  • Tea tree oil contains varying amounts of 1,8–cineole, a skin irritant. Products with high amounts of this compound may cause skin irritation or contact dermatitis, an allergic reaction, in some individuals. Oxidized tea tree oil (oil that has been exposed to air) may trigger allergies more than fresh tea tree oil.
  • Tea tree oil should not be swallowed. Poisonings, mainly in children, have caused drowsiness, disorientation, rash, and ataxia—a loss of muscle control in the arms and legs causing a lack of balance and coordination. One patient went into a coma after drinking half a cup of tea tree oil.
  • Topical use of diluted tea tree oil is generally considered safe for most adults. However, one case study did report a young boy who had developed breast growth after using a styling gel and shampoo that contained both lavender oil and tea tree oil.
  • Tell all your health care providers about any complementary health practices you use. Give them a full picture of what you do to manage your health. This will help ensure coordinated and safe care.
And the University of Maryland Medical Centre says this about lavender oil:
  • A small study published in the New England Journal of Medicine in 2007 concluded that lavender and tea oils in some shampoos, soaps, and lotions may cause gynecomastia, breast development in a male, in boys. 
  •  Lavender oil is toxic if taken orally.
  • There are no known scientific reports of interactions between lavender and conventional medications. However, because lavender promotes relaxation, it may make the effects of central nervous depressants stronger.
2. Effective once doesn't mean effective always.
It is now common knowledge around lice circles (though seemingly not common knowledge with our local school systems and public health authorities) that permethrin/pyrethrin based products, like Nix, have lost their effectiveness.  There are other products that are also losing their effectiveness and tea tree oil has also lost effectiveness in some parts of the world.  Lice researcher, Ian Burgess says, "‘Tea tree oil has a component that works in the same way as the insecticide malathion, so lice are also resistant to it.’  My own anecdotal offering is that I have been to many, many homes where people have tried a variety of products that include tea tree oil with no success. 

When trying to get rid of head lice, we often grasp for any miracle cure, and if that cure seems natural, then we often buy into it hook, line, and sinker.  You know my thoughts about this.  If you choose to use any "shampoo", you will still need to do manual lice and nit removal.  But manual removal, done with a proper comb on wet, conditioned hair is also proven to be very effective.  And it is much cheaper.  You know my vote.  Skip the tea tree oil.