Oregano oil
Also called: Oil of oregano, Origanum vulgare, carvacrol
A strong essential oil from wild oregano with antimicrobial compounds such as carvacrol. It is meant for short-term use and can irritate the mouth, skin, and stomach.
Commonly used for
- Short-term gut balance protocols
- Short-term support during colds
- Sinus and throat support
Found naturally in
- Oregano leaf, used as a culinary herb (much milder than the oil)
Label red flags
- Carvacrol content not listed
- Undiluted oil sold for swallowing
- Products meant for daily, year-round use
Check with a provider
- Pregnancy or breastfeeding: avoid
- Allergy to mint-family plants, such as basil, mint, sage, or lavender
- Taking blood thinners or diabetes medicine
- Iron deficiency. It may reduce iron absorption, so separate it from iron supplements.
- Long-term use may disturb healthy gut bacteria
Supplements that contain it
Parts of the body it affects
Explore what each area does and the conditions that can affect it.

Digestive tract
Your stomach and intestines absorb nutrients and hold most of your body's immune tissue, which makes the gut a common target in autoimmune disease.

Blood & immune system
Blood carries oxygen and nutrients, and white blood cells defend you from infection. In autoimmune disease, that defense system targets your own tissues.
Illustrations: Servier Medical Art, CC BY 4.0

Wondering if your symptoms fit a pattern?
Dr. Lesher is a naturopathic doctor who specializes in women's autoimmune and chronic conditions. Since 2020, she has helped more than 900 patients overcome and heal from their conditions.