What about COVID-19 and essential oils?

Long-time readers know that my “go-to” sources for natural medicines (herbs, vitamins, and supplements) are ConsumerLab.com and Natural Medicines(TM). ConsumerLab has posted about coronavirus and essential oils. But before I get to the specifics, I’ve also blogged in the past about essential oils in the past:

But what about essential oils? Do they help prevent or treat COVID-19? ConsumerLab.com writes:

Essential oils from plants such as eucalyptus, lavender, and tea tree have been shown in laboratory studies to have antiviral and/or other antimicrobial effects, as discussed below, but none have been shown to prevent or treat COVID-19 or other diseases caused by coronaviruses.

The FDA has recently sent warnings to several companies promoting essential oils for use in treating COVID-19. Be aware that many essential oils can irritate the skin and eyes and cause allergic reactions when used topically.

Some essential oils can have serious adverse effects if inhaled or cause severe toxicity if ingested. 

Eucalyptus oil 

Eucalyptus oil has been shown in laboratory studies to inhibit certain viruses, including HSV-1, influenza A (H1N1), and the mumps virus (Winska, Molecules 2019).

A limited number of small clinical trials have suggested that capsules containing cineole, a main constituent of eucalyptus oil, may be helpful for colds, viral sinusitis or asthma, but research has been limited due to side effects (i.e., nausea, heartburn, diarrhea and skin rash) and safety concerns (excessive doses can be fatal). 

Nevertheless, a product containing a blend of eucalyptus, orange, lemon and myrtle essential oils that have been double-distilled for purity (Myrtol) has been shown in several small placebo-controlled clinical trials to reduce symptoms of chronic and acute sinusitis and bronchitis with a low incidence of side effects, although one case of anaphylactic shock due to allergic reaction to an ingredient in the capsule has been reported (Paparoupa, Pharmacogn Rev 2016). 

Inhaling eucalyptus oil vapors is a common home remedy for colds and sinus infections. However, be aware that this can exacerbate asthma in some people.

Inhaling eucalyptus, as well as use of eucalyptus nasal drops and using eucalyptus on the skin has been reported to cause seizures in people without a history of seizures, as well as breakthrough seizures in people with well-controlled seizures (Mathew, Epilepsia Open 2017). 

Lavender oil 

Lavender oil has been shown in laboratory studies to inhibit bacteria known to cause respiratory infections and the virus HSV-1 (Roller, J Altern Complement Med 2009Winska, Molecules 2019).

However, there do not appear to be any clinical studies showing lavender oil to prevent or treat respiratory infections. 

Be aware that, taken orally, lavender oils and tinctures can cause stomach upset, nausea and headache (Schlafke, Phyomedicine 2010Akhondzadeh, Prog Neuropsychopharmacol Biol Psychiatry 2003).

Topical use of products containing lavender, and inhalation of lavender from diffusers has been associated with abnormal breast growth in children. 

Oregano oil 

Oregano oil has been shown in laboratory studies to have antibacterial and antiviral effects.

For example, it was shown to inhibit the norovirus (a virus that causes colds) in mouse cells (Gilling, J Appl Microbiol 2014).

However, there do not appear to be any studies on the effects of oregano oil to prevent or treat respiratory infections in people. 

In one small, company-funded study in people with parasitic intestinal infections, oregano oil tablets (200 mg of emulsified oregano oil) taken three times daily for six weeks reduced or eliminated the presence of parasites in stool in most of the participants.

However, the study did not include a placebo or a control group, so it does not prove that the treatment worked (Force, Phytother Res 2000). 

Be aware that non-emulsified oregano oil can irritate the lining of the digestive tract, and rarely, allergic reactions to oral consumption of oregano have been reported (Force, Phytother Res 2000Benito, Ann Allergy Asthma Immunol 1996). 

Tea Tree oil 

Tea Tree oil has been shown in laboratory studies to inhibit a variety of bacteria such as S. aureus and E. coli, certain fungi, and the virus that causes cold sores (HSV-1) (Carson, Clin Microbiol Rev 2006).

Used topically, tea tree oil has been shown to be helpful in treating acne and athlete’s foot.

However, be aware that when applied to the skin, tea tree oil can cause allergic reactions, rash, and inflammation in some people. 

Inhaling tea tree oil, or adding the oil to vaporizers, is sometimes recommended to help clear the sinuses or reduce congestion from colds and respiratory infections, but there is no direct evidence this would help in people with COVID-19. 

Preliminary laboratory research using tea tree oils showed some success in killing certain bacteria within 10 to 60 minutes, but the study did not measure its effects against viruses (May, J Antimicrob Chemother 2000).

There is no evidence at this time that tea tree oil is an effective disinfectant or hand sanitizer to protect against SARS-CoV-2. 

Tea tree oil is poisonous if swallowed. It should never be taken orally.

Tea tree oil, even in small quantities, can be harmful and even fatal to dogs and cats, so do not leave tea tree oil on surfaces that pets can access (Khan, J Am Vet Med Assoc 2014). 

Other Safety Concerns with Essential Oils

Essential oils should never be taken orally by infants, children, or women who are pregnant or breastfeeding.

Essential oils from eucalyptus, rosemary, fennel, sage, hyssop, wormwood, camphor, spike lavender and possibly other plants should not be used by people with a seizure disorder (Epilepsy Society of the UK 2019). 

See the articles on ConsumerLab.com with information about other essential oils, including lemon balmsage, and sandalwood, and an article about aromatherapy. Also see their information about peppermint oil

Of course, the most important thing you can do to avoid infection with coronavirus is to prevent exposure by following the latest recommendations of the CDC and World Health Organization and take steps to stay healthy, including getting adequate sleep, keeping up with your daily exercise, and eating a healthy nutritious diet. 

© Copyright WLL, INC. 2020. This blog provides a wide variety of general health information only and is not intended to be a substitute for professional medical advice, diagnosis, or treatment from your regular physician. If you are concerned about your health, take what you learn from this blog and meet with your personal doctor to discuss your concerns.

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