DISCLAIMER: I am an ER nurse, but I’m also a midwife. As such, I straddle both “conventional” and “alternative” medicine. I use and recommend alternative pharmaceuticals (e.g., herbs, essential oils, homeopathic remedies, etc.), but I’m not above using conventional pharmaceuticals (e.g., antibiotics, lidocaine for stitches, etc.). I treat all pharmaceuticals, be they conventional or alternative, with the same pause, consideration, and concern. Please note this is not aimed at anyone in particular but rather at everyone who uses or is considering using essential oils. I do not pretend to be an expert on essential oils; I am just beginning my research. I merely hope to open some eyes to potential dangers with improper use and encourage people to begin doing their own research independently of any rep’s advice.
COMMENTS: People tend to get a little… uptight… dare I say defensive?… when discussing essential oils. Please see my About page for my comments policy.
Long story short, I’ve recently come to learn some specific things about proper use of essential oils (EOs) that most people don’t seem to know and the bad advice flying around has always bothered me, but it’s gotten much more bothersome lately. Maybe it’s because I’ve learned more about EO safety over the past couple months. Maybe it’s because I was recently given bad advice for treatment of my mastitis that could have harmed my newborn if I didn’t know better, which really brought home to me the risks people undergo just by having friends they trust who use EOs. I’ve also always been deeply irritated by people who claim or pretend to know more than they do and use their fake expertise or credentials to influence people who don’t know better. For example, during the Ebola “epidemic” in America, a couple of acquaintances of a friend were using their position in a hospital (which, coincidentally, did not involve any medical training whatsoever, but rather health insurance training, and zero patient contact, facts which no one who works outside of a hospital would know unless they specifically looked it up) to convince people that they knew what they were talking about when they said Ebola was more contagious than the flu or measles. (#facepalm #thisiswhydovescry) Similarly, many MLM EO reps who have little to no training (and what they do have is provided by others with little or no training or experience) use their fake credentials to convince clients that they know what they’re talking about when they say X use of X oil is safe in X person for X ailment, but they’re often wrong, putting others at risk with their bad advice, and never seem to be willing to admit they’re wrong, even arguing with aromatherapists (those who actually have undergone in-depth, unbiased training on essential oil use). There is also a much larger subset of people who have taken bad advice from others and, through no fault of their own, pass on that bad advice simply because they don’t know better and because they trust the person who gave it to them. It’s been said that the most dangerous place to be is where you have just enough knowledge to give you confidence in your practice but not enough to recognize when your practice is dangerous. So maybe I’m writing this because I resent it when those with little or no education use their dangerous level of knowledge to influence others to do dangerous things—and then argue with those who actually have the education to know the truth. At any rate, whatever my reason for writing this blog post, consider this a PSA.
(As a side note, this risk of bad advice and potential harm is true of virtually any alternative medicine. I’ve had pregnant clients receive recommendations for herbs that I knew to be abortifacient. Luckily, being a midwife and having taught classes on birth control, which includes abortifacients, I knew better and could advise against it, but many people wouldn’t know better and would blindly take those herbs while pregnant and potentially miscarry.)
I know this post is going to tick off a bunch of people (mostly MLM EO reps), but I’m an ER nurse and, as such, am not afraid to tell someone, “You’re being unwise with certain aspects of your healthcare and may seriously harm yourself or your child with some of these uninformed decisions.” (Of course, in the ER, it was often more along the lines of, “Dear God, you’re such an incomparable moron. How are you still living?” Slightly different situation. But the point is that I learned a little bit about bravery in regards to telling people the truth about their health.) Some of this may seem overly cautious, but if you don’t know all the cautions, then you can’t make a truly informed decision. It may seem overly cautious to tell someone who has been taking narcotics daily for decades that they’re not supposed to drive while on narcotics, but if I as an ER nurse didn’t offer that education, that would be considered bad practice, and if that person then got into a car accident, I would be liable in a malpractice suit. Ditto the failure to educate a patient taking an antifungal pill regarding potential liver damage from drinking alcohol while taking the drug, or any other number of potential risks with conventional medicine. What you do with the education provided here is up to you. But at least my conscience will be clear and your eyes, hopefully, will be opened to the potential dangers of the extremely potent alternative medicine known as essential oils and you will gain a new respect for this potentially harmful and potentially beneficial “wonder drug.”
What is It?
EOs have been used for thousands of years in humans to treat a variety of conditions. As such, it’s difficult to patent and therefore difficult to obtain research grants because of the risk of no return on investment. It also means many of the EO remedies have been tested by time. On the other hand, it has sometimes taken thousands of years to abandon bad medical practices from the past, so just because a practice is very old doesn’t mean it’s good.
Nevertheless, in this case, there’s plenty of scientific evidence indicating that EOs are beneficial for the treatment of various conditions when used correctly (however, remember to take all studies on any topic by any author with a grain of salt, understanding that it’s extremely easy to publish fraudulent studies and that most published research is false ). For example, the University of Minnesota has an article  on EO research wherein it asserts that EOs have shown “positive effects for a variety of health concerns including infections, pain, anxiety, depression, tumors, premenstrual syndrome, nausea, and many others” and then lists 75 published research studies for a brief glance at the literature on the topic. The book Essential Oil Safety by Robert Tisserand reportedly lists over 4,000 studies.
Ok… But what **are** they? Basically, EOs are super-concentrated herbs in oil form. EOs are far more potent than dried herbs. In fact, one ounce of EO may have literal tons of plant matter and be over 100x the strength of its herbal version. EOs are extremely potent, then, and pose a high risk of chemical reactions if used incorrectly or unwisely. Which brings us to the next topic…
EO Dangers and Sensitization
EOs pose similar risks to those you’d expect from any highly concentrated substance. For example, dermatologists sometimes recommend a bath with half a capful of bleach to treat childhood eczema, but touching undiluted bleach can give you a chemical burn. As another example, vitamin C is relatively harmless, but it’s still an acid—in fact, I once burned the roof of my mouth by sucking on a low-dose (500 mg) vitamin C tablet. EOs are similar. A given EO may be harmless at a certain dilution but cause serious harm if undiluted.
Perhaps the most commonly discussed risk with EOs is “sensitization.” The West Coast Institute of Aromatherapy  and aromatherapist Lea Harris of LearningAboutEOs.com  explain what this is. Basically, many EOs can cause skin irritation, and this typically occurs on the first use. However, sensitization is basically an allergic reaction. Like all allergic reactions, it’s typically *not* the first use that causes a visible reaction (in fact, I had taken Vicodin off and on for years for various ailments before I first developed an allergic reaction to it; sometimes it takes one use, but other times it takes years to develop an allergic response). Sensitization is more likely in those with sensitive skin (e.g., eczema, infants, etc.) and is typically associated with undiluted (“neat”) use or overuse (e.g., lavender is considered one of the safest EOs, but aromatherapists most often become sensitized to lavender because they use it with their clients so frequently). This is why undiluted use is rarely recommended, and why it’s recommended you don’t use the same EO daily for a long period of time. Furthermore, if you are in a profession or have a career or side job that involves frequently handling essential oils (e.g., aromatherapist, massage therapist, seller of essential oil-infused soaps or lotions or other care products, etc.), you should strongly consider wearing gloves when handling oils so as to prevent sensitization to any oils, which may hamper or prematurely end your career, as it has for others (e.g., 14). Sensitization may occur with any EO and brand is irrelevant in the same way that if you’re allergic to peanuts, you’ll be allergic to all brands of peanut butter.
There are also some side effects associated with each EO that should be taken into consideration. For example, “thieves”-type blends typically contain cinnamon bark and clove, both of which are blood thinners; rosemary and eucalyptus, both of which can inhibit the respiratory drive in children (Footnote 1); and lemon and bitter orange, both of which are phototoxic (note that sweet orange, sometimes used instead of bitter orange, is not phototoxic) . Therefore, these additive—or even synergistic—effects make thieves blends unsuitable for people prone to bleeding (e.g., people taking blood-thinners), children under age 10, and people at risk of sunburn (e.g., fair-skinned people planning to be out in the sun for a significant length of time). Knowing about these side effects can help people avoid using an EO that might be fine for most but harmful for them.
What I’m trying to say is that EOs, like any medicine, must be treated with the respect they deserve. They are powerful medicinals and may indeed be that magic cure you’ve sought, but when used unwisely, they may do you serious harm.
There are some general guidelines for proper, safe use of EOs. You certainly have the right and ability to violate these guidelines, but you do so at your own (or your child’s) risk. My hope is only that you would be informed so that, at the least, you’re aware of the guidelines and know that what you’re doing is potentially dangerous—basically, that if something goes wrong, it won’t be because you were uninformed and your response won’t be that ever-heartbreaking “I didn’t know.”
Dilution and Mixing
EOs are most often diffused into the air and inhaled, but may be used topically (put directly on the skin). Some people also ingest EOs.
Diffusion is the safest way to use EOs, so it’s generally the first recommendation. However, topical application is generally safe when done correctly.
What is the correct way to use EOs topically? Generally speaking, the correct way to use them topically is to dilute them first in a carrier oil such as coconut oil. The term “neat” refers to undiluted topical application—i.e., putting the oil directly on your skin without first diluting it by mixing it in a carrier oil. Directly applying any undiluted, concentrated substance is rarely recommended, regardless of whether you’re cooking, cleaning, or formulating/administering medications as a nurse working in a hospital setting, and the same is true of EOs. Neat application is a particularly predictive risk factor for sensitization, as mentioned above, so should be avoided if at all possible. Neat application is NEVER recommended for children, whose skin is far more sensitive and absorbent than that of adults and who therefore are at significantly increased risk of having reactions to topical EOs, including sensitization. Neat application is almost never indicated for adults, either. Furthermore, EOs are actually spread and absorbed better when diluted in a carrier oil, and many carrier oils have additive or synergistic effects due to their own therapeutic properties (for example, coconut oil is antiinflammatory). Therefore, EOs are generally more effective when diluted prior to topical application and are more likely to cause problems if not diluted before topical use [6,7,8,10].
How much should they be diluted? That depends on the age of the patient and the purpose of the treatment, but the concentration of the oil ranges from 0.25% (1 drop EO to 4 tsp carrier oil) to 2% (2 drops per tsp). For very short-term use in adults, 3% concentration or even 25% concentration may be used. Exceptionally rarely, an EO may be used neat in adults. Check out Lea Harris’s article for more information on dilution .
Now, as for ingestion… The mucous membranes of your mouth, throat, etc., allow absorption much more readily and are much more sensitive to bad side effects of EOs. When used topically, you absorb about 10% of the dose, but when swallowed, you absorb about 95%, which goes straight to (and can accumulate in) your liver, so there’s also a risk of what amounts to overdose with ingestion. Remember that essential oils are extremely potent. Swallowing a drop of EO is NOT the same as swallowing an herbal pill or two. One drop of EO is FAR more potent than a couple pills of herbs.
Aromatherapist Lea Harris warns, “Physical contact of essential oils on the mucous membranes can cause immediate irritation, or even burns. Long-term consequences of allowing essential oils to physically touch this delicate skin can lead to permanent damage, including scarring and ulcers, as well as liver and/or kidney damage, and the potential for cancer.”
Aromatherapists will very rarely agree that ingestion is safe or preferable. If you wish to ingest it, though, you should do so only under the guidance of a certified aromatherapist and you should first dilute it in a carrier oil and put it in a capsule so that when you swallow the pill, the EO bypasses your most sensitive tissues and will be diluted when it does contact your mucous membranes.
EOs should NEVER be added to water and drunk. Oil and water does not mix. In other words, the oil is being placed directly against your sensitive mucous membranes—you might as well have swallowed the EO directly without adding it to your water because it has the same undiluted effect. An EO added to water is NOT diluted because oil and water do not mix.
Again, brand doesn’t matter—ALL EOs are highly concentrated and therefore pose a risk of chemical irritation and sensitization. 
There are also lots of oils that should not be used in children of certain ages. As a general rule:
- Under 3 months: NO EO use in any form (Footnote 2)
- Under 2 years: preferably no EO use, with hydrosols and herbs preferred over EOs due to greater risks with EOs; generally only diffusion permitted (if used at all), though the extremely rare topical use may be recommended (e.g., for treatment of bug bites)
- Under 6 years: very limited EO use; diffusion and topical permitted
- Under 10 years: diffusion and topical permitted
There are many EOs that are not safe for use in any form in children of certain ages. For a list of EOs not recommended for each age, here’s a quick, reader-friendly cheat sheet.
As with drugs, children are more sensitive to the effects of EOs, are at higher risk of overdose, metabolize EOs differently, and absorb more of a topically applied dose as compared to adults. Their skin is also more sensitive (consider, for example, how many infants react to various laundry detergents as compared to older children and adults), and so are at higher risk of skin irritation and reactions—including sensitization—than adults, even if the EO is used correctly, which demonstrates the importance of very judicious use of EOs in children, especially young children and infants. You wouldn’t give a 2-year-old 800 mg of ibuprofen. Similarly, I hope you would think twice about using EOs on your small child—and preferably choose the less concentrated and therefore safer hydrosols or herbs instead. [10,11]
Some EOs, like the herbs from which they come, may cause birth defects or miscarriage, and some may enter the breastmilk. Like drugs, most EOs have unknown safety profiles in pregnancy or breastfeeding and so should generally be avoided in pregnancy unless absolutely necessary and used with caution while breastfeeding. Neat (undiluted) and internal (swallowed) use in pregnancy and breastfeeding is never recommended. 
Just because it’s “natural” doesn’t mean it’s safe. Remember that some herbs can cause miscarriages and birth defects and that EOs are super-concentrated herbs that are over 100x more powerful. Therefore, the risk for untoward effects on the unborn baby is great.
Furthermore, something most people don’t seem to talk about is that an EO may be safe for an adult but not safe for an infant, and so a woman who is breastfeeding shouldn’t use such an EO topically in an area where her nursing infant might breathe or touch. For example, a friend recommended I use two EOs topically on my armpits when I had mastitis. However, my baby was only a couple weeks old at that point—far younger than the minimum age for EO inhalation of 3 months and EO topical use of 2 years—and if I did as recommended, there was a risk that my newborn would both inhale and potentially touch the EOs on my skin. Luckily, I knew enough to seek advice from an aromatherapist before following my friend’s advice, but most people wouldn’t know better and would put their newborns at risk. The same friend recommended putting a blend on my feet to treat the mastitis. Though the effectiveness of such a use is in question, my newborn wouldn’t be smelling or touching my feet, so that would be a safe use as regards my baby (assuming all the oils in the blend are otherwise considered safe when breastfeeding—which, coincidentally, they were not).
For a list of EOs not recommended in pregnancy and breastfeeding, there’s another quick, reader-friendly cheat sheet on the same page as the children’s cheat sheet.
If you’re the type of person to blindly swallow whatever pills any doctor prescribes you, no one (well, very few people, anyway) would think you a hypocrite for blindly following the advice of friends more knowledgeable than yourself as regards EO use. However, if you are the kind of person to avoid overuse of conventional medicine (e.g., antibiotics for every infection, antipyretics for fevers, etc.), to use natural or alternative medicine due to a belief that it is safer, to think twice before adding a new prescription to your list, to research drug reactions before agreeing to a new drug, or at the very least to hesitate when given a pharmaceutical recommendation from a healthcare professional, but you don’t hesitate when given an essential oil recommendation by a friend, even a very knowledgeable friend, then you are practicing alternative medicine dangerously. As with all alternative medicine, educate yourself prior to use, generally avoid use if not needed, and don’t blindly follow ANY advice. I always recommend that you err on the side of caution. YOU (or your child) are the one who will have to live with the consequences of bad advice followed blindly.
Footnote 1: Eucalyptus and Rosemary Inhibit Respiratory Drive in Children. This is widely agreed upon among aromatherapists and written in basically every aromatherapy textbook. However, there are some who disagree with this. See here for more information if interested.
Footnote 2: No EO Use in Infants Under 3 Months of Age. It’s unknown what age is actually safe for EO use. However, Robert Tisserand talks about how infants reach a developmental milestone as regards skin permeability and sensitivity to EOs around 3 months of age. For this reason, many don’t recommend use under age 3 months, but consider 3+ months to be “probably safe” for very limited, properly diluted use (e.g., 13).
- Ioannidis, J.P.A. (2005). “Why most published research findings are false.” PLoS Med, 2(8):e124. doi: 10.1371/journal.pmed.0020124. Retrieved from <http://journals.plos.org/plosmedicine/article?id=10.1371/journal.pmed.0020124>
- Halcón, L. (N.d.) “What does the research say about essential oils?” University of Minnesota. Retrieved from <http://www.takingcharge.csh.umn.edu/explore-healing-practices/aromatherapy/what-does-research-say-about-essential-oils>
- West Coast Institute of Aromatherapy (N.d.) “Essential Oil Safety–Skin Sensitization.” Retrieved from <http://www.westcoastaromatherapy.com/free-information/articles-archive/essential-oil-safety-skin-sensitization/>
- Harris, L. (2014). “A Word on Sensitization.” LearningAboutEOs.com. Retrieved from <http://www.learningabouteos.com/index.php/2014/03/12/a-word-on-sensitization/>
- Harris, L. (2014). “Thieves & OnGuard essential oil blends – what you must know before using thieves-type blends.” LearningAboutEOs.com. Retrieved from <http://www.learningabouteos.com/index.php/2014/08/17/thieves-onguard-essential-oil-blends-what-you-must-know-before-using-thieves-type-blends/>
- Harris, L. (N.d.). “Undiluted Essential Oils For Babies: Busted Essential Oil Myth #3.” Food Renegade. Retrieved from <http://www.foodrenegade.com/undiluted-essential-oils-for-babies-busted-essential-oil-myth-3/>
- Harris, L. (2014). “Neat Babies – Are there consequences to using essential oils “neat” on your children?” LearningAboutEOs.com. Retrieved from <http://www.learningabouteos.com/index.php/2014/10/02/neat-babies/>
- Harris, L. (2013). “Properly Diluting Essential Oils.” LearningAboutEOs.com. Retrieved from <http://www.learningabouteos.com/index.php/2013/08/07/properly-diluting-essential-oils/>
- Harris, L. (2013). “Ingesting Essential Oils.” LearningAboutEOs.com. Retrieved from <http://www.learningabouteos.com/index.php/2013/08/06/ingesting-essential-oils/>
- Harris, L. (2014). “Safely Using Essential Oils for Children.” Herbal Academy of New England. Retrieved from <http://herbalacademyofne.com/2014/08/using-essential-oils-for-children/>
- Harris, L. (2014). “Essential Oils and Children.” LearningAboutEOs.com. Retrieved from <http://www.learningabouteos.com/index.php/2014/02/07/essential-oils-and-children/>
- Harris, L. (2013). “Essential Oil Safety During Pregnancy.” LearningAboutEOs.com. Retrieved from <http://www.learningabouteos.com/index.php/2013/08/06/essential-oil-safety-during-pregnancy/>
- Anthis, C. (2014). “Safe Essential Oil Use with Babies & Children.” The Hippy Homemaker. Retrieved from <http://www.thehippyhomemaker.com/essential-oil-safety-babies-children/>
- The Untamed Alchemist (2015). “Put Essential Oils in ALL the Things! (Yeah, NO.)” Retrieved from <http://theuntamedalchemist.com/2015/02/15/put-essential-oils-in-all-the-things-yeah-no/>