From MEpedia, a crowd-sourced encyclopedia of ME and CFS science and history

Oregano is an herb, which includes a variety of plant species, that is used, in addition for flavor in cooking, for its antimicrobial effects.[1] It is of particular interest as a treatment for Small Intestine Bacterial Overgrowth (SIBO),[2] which can be a comobidity in people with ME/CFS.

Forms[edit | edit source]

Oregano is available as "Oil of Oregano", an essential oil which contains concentrated chemical compounds extracted from the leaves of the oregano plant. The oil has a strong scent and flavor that is very similar to the common oregano spice, but much stronger. A drop of the oil on skin or in the mouth produces a warming or burning sensation. Instructions for dosing typically recommend diluting the oil with an inert carrier oil, such as Olive Oil, to reduce the sensation. Dosage recommendations vary by source, but are typically a few drops administered two or more times per day.

Oregano is also available as capsules containing dried oregano leaves.

Evidence[edit | edit source]

Anti-bacterial[edit | edit source]

Oregano has demonstrated anti-bacterial effect on many species of gram positive bacteria in both essential oil and infusion forms.[1]

Treatment for SIBO[edit | edit source]

A retrospective chart review published in 2014 compared an herbal therapy protocol (which included Oregano) to therapy with the synthetic antibiotic Rifaximin. Efficacy of the herbal therapy, as measured by Lactulose breath test conducted post-treatment, was superior.[2] The study included patients newly diagnosed with SIBO, and patients in each group were treated for 4 weeks. The study had several important caveats:

  • The herbal protocol included a mix of herbs, not oregano alone.
  • The Rifaximin group was administered only 1200 mg per day, whereas the dosage in for SIBO treatment is typically 1650 mg / day.
  • It was not a prospective or randomly controlled trial.

Safety & Side Effects[edit | edit source]

  • May cause reactions in people who are alergic to plants in the Lamiaceae family, which includes basil, hyssop, lavender, marjoram, mint, and sage.[3]
  • May increase risk of bleeding. This concern is emphasized for people with bleeding disorders or undergoing surgery.[3]
  • May lower blood sugar. Therefore people with diabetes should exercise additional caution.[3]
  • May cause miscarriage if taken in medicinal amounts.[3]
  • Safety when breastfeeding is unknown.[3]
  • May cause irritation of the skin if applied in concentrations greater than 1%.[3]

Cost and Availability[edit | edit source]

United States[edit | edit source]

In the United States, both Oregano capsules and Oil of Oregano are available without a prescription. The cost of a bottle of Oil of Oregano is in the low tens of dollars and contains a 2-4 week supply, assuming typical dosing.

Learn more[edit | edit source]

References[edit | edit source]

  1. 1.0 1.1 Saeed, Sabahat; Tariq, Perween (October 2009). "Antibacterial activity of oregano (Origanum vulgare Linn.) against gram positive bacteria". Pakistan Journal of Pharmaceutical Sciences. 22 (4): 421–424. ISSN 1011-601X. PMID 19783523.
  2. 2.0 2.1 Chedid, Victor; Dhalla, Sameer; Clarke, John O.; Roland, Bani Chander; Dunbar, Kerry B.; Koh, Joyce; Justino, Edmundo; Tomakin, Eric; Mullin, Gerard E. (May 2014). "Herbal Therapy Is Equivalent to Rifaximin for the Treatment of Small Intestinal Bacterial Overgrowth". Global Advances in Health and Medicine. 3 (3): 16–24. doi:10.7453/gahmj.2014.019. ISSN 2164-957X. PMC 4030608. PMID 24891990.
  3. 3.0 3.1 3.2 3.3 3.4 3.5 "Oregano Effectiveness, Safety, and Drug Interactions on RxList". RxList. Retrieved June 1, 2019.