Methicillin-resistant Staphylococcus aureus (MRSA) and other antibiotic-resistant bacteria are big problems. They account for millions of illnesses, thousands of deaths and billions of dollars in costs every year internationally. Antibiotic-resistance is a complex issue, but some people try to over-simplify (and under-analyse) the problem.

A recent article on is an example. Entitled "MRSA cases double in five years while natural solution is overlooked", the article – while providing very little real information – claims that essential oils are "unmatched tools in the fight against MRSA."

  • It talks about the bacterial killing power of essential oils. That’s certainly true. Many essential oils are potent antibacterial substances.
  • It also claims that essential oils are "free of the side-effects common to antibiotics." That’s not so true. In fact, essential oils can be quite toxic. Tea tree oil, one of the more popular essential oils, can cause a range of adverse effects, and I’m aware of a couple of dogs that have died from suspected tea tree oil toxicity. A study presented at the North American Dermatology Forum last fall (Valentine et al.) showed that while some essential oils were effective against resistant staphylococci, they also had damaging effects on canine skin cells. One oil had essentially no antibacterial effect but did a lot of damage to skin cells.

The antibacterial effects of essential oils might be useful, but only if they do no damage to the animal (or person) at the same time. The problem is these products are not technically sold as drugs, despite the fact that they are really marketed as drugs, so they bypass the requirement to demonstrate safety and effectiveness. If a product showed good antibacterial activity and no toxicity, it would be a potential option for the treatment of superficial infections, but in the absence of proper testing demonstrating safety, I wouldn’t use an essential oil, as it may do more harm than good.

The article doesn’t contain much useful information and is more of an infomercial than anything else. It highlights on particular company called Young Living Essential Oils. The author of the article also seems to be that company’s "Product Training Program Manager," according to articles he’s also written on the website. No conflict of interest there, obviously!

A complex problem like antimicrobial resistance requires complex solutions. Non-antimicrobial options are one part of this, which is why my lab has done work in this area. However, all-natural doesn’t necessarily mean safe or effective, and we need to demand proper testing of such products. Too many companies take the cheap and easy way out and don’t do any testing. While they may make money, their customers (and their pets) are the ones who can end up paying the price.