Nutritional Supplement

Oregano/Wild Marjoram

Also indexed as: Origanum vulgare, Marjoram (Wild), Oreganol

Side Effects

Oregano leaf is very safe. The German Commission E and American Herbal Products Association both state there are no known risks with oregano leaf;21 neither of these references mentions oregano oil.

Due to the lack of human research and the highly concentrated nature of oregano volatile oil, there is potential for harm from its use; therefore, until its internal use in humans has been proven safe, it should taken with caution if not recommended by a healthcare professional.22 Volatile oils are generally considered contraindicated in pregnancy as they likely reach the baby and may cause harm.23 Topically, the volatile oil of oregano may be moderately irritating to skin and can be a potent mucous membrane irritant. It should not be applied topically to mucous membranes in greater than a 1% concentration.24 Children less than two years of age and people with damaged or very sensitive skin should not use the oil topically.24

References

1. Leung AY, Foster S. Encyclopedia of Common Natural Ingredients, 2nd ed. New York: John Wiley & Sons, 1996, 398-9.

2. Wren RC. Potter's New Cyclopedia of Botanical Drugs and Preparations. Essex, England: C.W. Daniel, 1985, 185.

3. Leung AY, Foster S. Encyclopedia of Common Natural Ingredients, 2nd ed. New York: John Wiley & Sons, 1996, 398-9.

4. Stiles JC, Sparks W, Ronzio RA. The inhibition of Candida albicans by oregano. J Applied Nutr 1995;47:96-102.

5. Hammer KA, Carson CF, Riley TV. Antimicrobial activity of essential oils and other plant extracts. J Appl Microbiol 1999;86:985-90.

6. Ponce MM, Navarro AI, Martinez GMN, et al. In vitro effect against Giardia of 14 plant extracts. Rev Invest Clin 1994;46:343-7 [in Spanish].

7. Tantaoui EA, Beraoud L. Inhibition of growth and aflatoxin production in Aspergillus parasiticus by essential oils of selected plant materials. J Environ Pathol Toxicol Oncol 1994;13:67-72.

8. Blumenthal M, Busse WR, Goldberg A, et al. (eds). The Complete German Commission E Monographs: Therapeutic Guide to Herbal Medicines. Boston, MA: Integrative Medicine Communications, 1998, 358-9.

9. Forster HB, Niklas H, Lutz S. Antispasmodic effects of some medicinal plants. Planta Med 1980;40:303-19.

10. Blumenthal M, Busse WR, Goldberg A, et al. (eds). The Complete German Commission E Monographs: Therapeutic Guide to Herbal Medicines. Austin: American Botanical Council and Boston: Integrative Medicine Communications, 1998, 425-6.

11. Weiss RF. Herbal Medicine. Beaconsfield, UK: Beaconsfield Publishers Ltd, 1988, 185-6.

12. Blumenthal M, Busse WR, Goldberg A, et al. (eds). The Complete German Commission E Monographs: Therapeutic Guide to Herbal Medicines. Austin: American Botanical Council and Boston: Integrative Medicine Communications, 1998, 198.

13. Stiles JC, Sparks W, Ronzio RA. The inhibition of Candida albicans by oregano. J Applied Nutr 1995;47:96-102.

14. Hammer KA, Carson CF, Riley TV. In-vitro activity of essential oils, in particular Melaleuca alternafolia (tea tree) oil and tea tree oil products, against Candida albicans. J Antimicrobial Chemother 1998;42:591-5.

15. Stiles JC, Sparks W, Ronzio RA. The inhibition of Candida albicans by oregano. J Applied Nutr 1995;47:96-102.

16. Hammer KA, Carson CF, Riley TV. In-vitro activity of essential oils, in particular Melaleuca alternafolia (tea tree) oil and tea tree oil products, against Candida albicans. J Antimicrobial Chemother 1998;42:591-5.

17. Stiles JC, Sparks W, Ronzio RA. The inhibition of Candida albicans by oregano. J Applied Nutr 1995;47:96-102.

18. Grieve M. A Modern Herbal, vol II. New York: Dover Publications, 1982, 520-1.

19. Castleman M. The Healing Herbs. Emmaus, PA: Rodale Press, 1991, 275-6.

20. Peirce A. Practical Guide to Natural Medicines. New York: William Morrow and Co., 1999, 476-7.

21. Blumenthal M, Busse WR, Goldberg A, et al, eds.The Complete German Commission E Monographs: Therapeutic Guide to Herbal Medicines. Boston: Integrative Medicine Communications, 1998, 358-9.

22. McGuffin M, Hobbs C, Upton R, Goldberg A, eds. American Herbal Products Association's Botanical Safety Handbook. Boca Raton, FL: CRC Press, 1997, 80.

23. Tisserand R, Balacs T.Essential Oil Safety. New York: Churchill Livingston, 1996, 234-5.

24. Tisserand R, Balacs T. Essential Oil Safety. New York: Churchill Livingston, 1996, 156-7.

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The information presented by TraceGains is for informational purposes only. It is based on scientific studies (human, animal, or in vitro), clinical experience, or traditional usage as cited in each article. The results reported may not necessarily occur in all individuals. For many of the conditions discussed, treatment with prescription or over the counter medication is also available. Consult your doctor, practitioner, and/or pharmacist for any health problem and before using any supplements or before making any changes in prescribed medications. Information expires December 2025.