When our contributing editor Andrew Rubman, ND, medical director of the Southbury Clinic for Traditional Medicines, suggests that we warn you about natural plant compounds…we listen. After all, as a naturopathic doctor, he’s all about using nature’s ingredients to promote health and treat disease.

But he called us recently with a serious concern about our readers’ safety when they use essential oils to treat health conditions. Essential oils are powerful, sometimes too powerful…unless you know how to use them right.

One reason he’s concerned is that we’re using them more than ever. Sales of these highly concentrated extracts of biologically active plant compounds have skyrocketed…nearly doubling in the last five years. In a time when people are looking for alternatives to pharmaceuticals, they are appealing as natural medicine. Lavender is used to treat insomnia and depression…tea tree oil for acne and wound healing…peppermint is a decongestant…rosemary is used for headaches…and lemon essential oil is said to stop hair loss and strengthen gums.

Yet few people appreciate how potent they are—a single drop of essential oil contains the amount of active compound that would be found in 15 to 40 cups of medicinal tea. Rub essential oils on your skin, and they get absorbed into your bloodstream. Breathe them in via aromatherapy, and they can directly affect your brain’s limbic system, which controls emotions.

“Essential oils can have profound effects on the central nervous system—it’s time we treated them with respect,” says Dr. Rubman. “Many people think they understand how to use essential oils therapeutically, but in my experience, most don’t.”


Essential oils have become popular for a wide variety of purposes, but they can also cause harm. In the medical literature, there are common reports of serious skin problems, sun sensitivity and even seizures…sometimes fatal ones. For example:

• Essential oils such as thyme, oregano, clove and cinnamon can irritate the skin—even cause blisters.

• Essential oils in the citrus family (bergamot, lemon, lime, orange, angelica) as well as cumin can cause phototoxicity…resulting in a burn when you’re exposed to the sun (or radiation from a sunbed) even briefly.

• Some essential oils can trigger seizures in people with epilepsy…including eucalyptus, fennel, hyssop, pennyroyal, rosemary and sage.

• Still others may interact with medications—peppermint and eucalyptus, for example, can interfere with the effectiveness of the cancer drug 5-fluorouracil.

• Allergic reactions are also possible. For example, if you are allergic to ragweed, you may be allergic to the essential oil of chamomile, which is in the same botanical family.

The good news is that serious issues are rare. “Most uses of essential oils are safe,” says Dr. Rubman. For reasons explained below, you don’t need to be concerned when your masseuse rubs oil that smells faintly like lavender or peppermint on your skin, or if you go into your gym’s sauna room and inhale the bracing aroma of eucalyptus.


Whether you are using essential oils for aromatherapy or rubbing them on your skin, you can enjoy their benefits safely by following these tips…

• Nearly all adverse effects have come from applying essential oils to the skin. For massage oil, dilution is essential. Rule of thumb—1% to 5% max. Says Dr. Rubman, “Play it safe, and dilute any essential oil for your skin in a carrier oil like sesame or coconut.” It’s still effective. In one study, lavender essential oil, diluted to 2% in peanut oil and used in a “gentle abdominal massage,” led to peak levels of active lavender compounds in the bloodstream about 30 minutes later.

• Aromatherapy is generally safe—but should still be diluted. Follow directions, including diluting essential oils to no more than 1% to 5% concentration in water or carrier oil.

• Use essential oil only on clean, unbroken skin—and never internally or as eyedrops.

• Children and pregnant women should avoid essential oils unless using them under the direction of a doctor.

• If you have a specific health concern, work with a naturopath or another doctor who knows about essential oils. Don’t rely on your masseuse to “treat” your problem.

Follow these tips and you can enjoy the benefits of essential oils—safely. To learn more about the uses of essential oils, including their benefits, see Bottom Line’s Make Your Home Smell Better, Aromatherapy’s Amazing Effects on Your Mind and Mood, and Elevate Your Massage (or Day) with Essential Oils.