Oregano oil Side Effects: What Reddit Users Report
21 of 494 Reddit owner comments about Oregano oil (4%) describe an unwanted effect. The effects people mention most are gas or bloating, nausea and loose stools or diarrhea. These are self-reports from Reddit IBS and gut communities (November 2025 to October 2026), not a measured side-effect rate, and many people report no problems at all.
Oregano oil overall: 3.8 · tolerability 4.7 (higher means fewer unwanted-effect reports).
What people describe
| Effect mentioned | Owner comments |
|---|---|
| Gas or bloating | 5 |
| Nausea | 3 |
| Loose stools or diarrhea | 3 |
How we counted: among the 21 comments that describe an unwanted effect, a category counts when a sentence names the effect with wording like "gave me" or "made me". Questions and sentences about an effect going away are skipped. One comment can count in more than one row, and keyword counts can include some unrelated mentions, so read the quotes below for context.
Most common complaints
- Side effects: 15 owner comments
- Bloating & gas: 7 owner comments
- Pain & cramping: 5 owner comments
Safety notes from NIH and published research
- Herbal antimicrobials are concentrated products. Tell your doctor before using them, especially if you are pregnant or take other medicines.[NIH Office of Dietary Supplements]
Stop and talk to a doctor if an effect is severe or does not settle. Ask a pharmacist about interactions with any medicine you take.
In their words
1/5 Side effects“I didn’t notice much help from herbal antimicrobials like oregano oil and it gave me horrible reflux.”
2/5 Side effectsStopped working“Tried natural antibiotic cause i suspected sibo, oregano oil cause nausea, caprylic acid didn’t seem to give me any reaction, berberine made me back to have a few food intolerance again.”
2/5 Side effects“Oregano oil didn’t help and it kinda made me nauseous actually”
4/5 Bloating & gasDie-off“Basically, yes, and 1 month before current protocol, i was taking oregano oil until I stopped feeling die-off symptoms.”
2/5 Side effects“imo different people tolerate different medicine/herbals, for example I tolerate oregano oil well which is unusual but have stopped two berberine trials due to side effects - which is unusual too.”
2/5 Side effects“Be careful with oregano oil, it can make your issues much MUCH worse, and cause a greater imbalance.”
2/5 Side effectsUrgency & loose stools“However i feel anxious to take mct oil and oregano oil.”
2/5 Bloating & gasDie-off“In my case I was dealing with a lot of gas/diarrhea, which became worse while taking the oil of oregano, but I think it was a combination of die-off and potency of the oregano itself.”
Frequently asked
What side effects do people report with Oregano oil?
21 of 494 Reddit owner comments about Oregano oil (4%) describe an unwanted effect; the ones mentioned most were gas or bloating, nausea and loose stools or diarrhea. These are self-reports, not a measured side-effect rate.
Is Oregano oil safe?
Safety depends on your health and medicines. The NIH and other sources listed on this page note specific cautions. Ask a doctor or pharmacist before starting, especially if you take other medicines or are pregnant.
More on Oregano oil
Compare side-effect reports: Allicin (Allimed / Allimax) vs Oregano oil · Berberine vs Oregano oil