T Nation

Oregano Oil


Hi all. I'm wondering if anyone has any strong opinions either way about supplementing with oregano oil regularly or just while sick (2-3 drops/day either way).

My literature searches have come up with some papers on it's antiviral properties and it's ability to restrain lipid oxidation in slaughtered meat, but no one's mentioned anything about us pesky humans. It's all the rage in the new age health magazines, but of course their usual version of proof is 'It works wonders!' and that's about it. Thoughts?


Bump(ing bastard that I am).


Oregano oil, in my opinion, should not be used or only with great caution. DEFINITELY not regularly. The new age health magazines probably do not mention that it contains volatile organic compounds (VOCs) that are toxic. One of these is thujone, a potent neurotoxin. Thujone is toxic to any living cell, particularly those in the liver, kidneys, and brain.

It is probably unlikely that a typical user would experience any lasting ill effects of the oil, but each bottle has an unknown amount of the harmful substances, and most likely no warnings to guide its use. From my research on thujone, I would guess that an amount of oregano oil that could have a true desired effect in vivo (e.g., antiviral, antifungal, antibacterial, anti-parasitic, etc.) would also have an unacceptably large undesired effect (e.g., liver damage). In other words, the safety-effectiveness ratio is not that good.

If you want to see if oregano oil has a desired effect for you, say antiviral, as good as is claimed, do an experiment on yourself by taking it when you have a viral infection, like a cold. I had many colds in my childhood and teens, and symptoms always lasted the standard 7-10 days no matter what I took. If I took oregano oil at the first sign of a cold and was symptom-free after 3 or 4 days, I'd be willing to use oregano oil temporarily as a cure for the cold virus. But I still wouldn't be surprised if it didn't work for a second cold; the first result could have been the placebo effect, or a short-lived flu rather than a cold, or an exceptionally potent batch of the oil, etc.

And I wouldn't use it long-term because 1) at any given time, I don't know the amount of harmful volatile organic compounds in a bottle of the oil, and 2) at any given moment, I don't know how good my liver is at detoxifying those compounds. I particularly don't know how #2 changes over time with exposure to #1.

In general, I would never personally orally ingest essential oils, period. I avoid using them topically as well; for example, I avoid sunscreens or other topical products that have long lists of essential oils in the ingredients. Many are irritating to skin.

There are many supplements with proven safety and health benefits, so I would focus my supplement budget on them.

Hope this helps.


Holy details Batman!

Thanks for the response Anderson, I appreciate the time you took.


Interesting...this paper actually says that it had positive effects on the liver.

Protective effect of volatile oil, alcoholic and aqueous extracts of Origanum majorana on lead acetate toxicity in mice.
Basic Clin Pharmacol Toxicol. 2005 Oct;97(4):238-43.

Natural dietary antioxidants are extensively studied for their ability to protect cells from miscellaneous damages. Origanum majorana L., Lamiaceae, is a potent antioxidant. The effect of administration of O. majorana (volatile oil, alcoholic and aqueous extracts) on oral administration of lead acetate in the diet of mice at concentration 0.5% (W/W) for one month were studied by measuring serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), urea and creatinine, histopathological changes of the liver and kidney and genotoxicity including, rate of micronucleus and chromosomal aberrations in bone marrow cells. Mice were treated with the 3 different forms of O. majorana, one month before and maintained with lead acetate administration. The 3 forms of O. majorana induced a significant decrease in serum activities of transaminases (AST & ALT), ALP, urea and creatinine and improved the liver and kidney histology in comparison with lead acetate treated group. Alcoholic extracts of O. majorana significantly reduced the rate of micronucleus, number of aberrant cells and different kinds of chromosomal aberrations. Volatile oil extract significantly reduced the rate of micronucleus and chromosomal fragments. Aqueous extract and volatile oil also of O. majorana significantly reduced number of gaps, ring chromosome and stickiness. It could be concluded that O. majorana plays an important role in ameliorating liver and kidney functions and genotoxicity induced by lead toxicity.


Sure, oregano oil may very well have positive or desired effects. But in this case, it only interacted with the concurrent administration of lead. It cannot be generalized that oregano oil is "good for the liver." It cannot even be generalized that oregano oil helps a liver suffering the effects of previous lead toxicity. Furthermore, the authors were looking for a specific protective benefit and did not at the same time look for other effects that might have been negative. For example, they did not report whether there was neurotoxicity of the GABA receptors. Given other literature, it is a possibility.

As incredible as it sounds, a friend of mine last fall nearly died from the effects of a supplement regime that included oregano oil. The oregano oil was not the greatest culprit, but it probably made some contribution. He was also enthusiastically using quite a bit of it, but overdose warnings were missing from every herbal label. And from the books and magazines he was reading, he knew nothing about possible negative effects. He naively believed any natural herb would be safe. Unfortunately, he has suffered permanent brain damage and kidney damage.

Maybe I'm being overly cautious because of this extreme case, but I would rather use other antioxidants until oregano oil has a recommended safe, effective dose demonstrated in human studies. I wouldn't go so far as to avoid meats preserved with oregano oil, but I wouldn't go out of my way to buy and take extra amounts orally either.


Maybe just eat a lot of oregano? Probably a lot cheaper, still very healthy, and without the potentially negative sides.

To boost immunity, also look into other anti-virals - like coconut oil, raw honey, raw crushed garlic.

If you mix those together and add some ginger/cayenne, and choke it back with some echinacea or cold FX, you'd be pretty solid.


Interesting to see the safety data.

I have used Oil of Oregano for the past year or so with no problems. The brand I use has specific dosing (4 drops per day), however I don't use it all the time. I would not think it wise to take anything with supposed anti-bacterial or anti-viral properties on a consistent basis. I have no evidence of this, but it seems it might wreak havoc on natural gut bacteria.

I have taken it with some success upon onset of colds, etc. Placebo effect? Perhaps, but I have done so numerous times and seem to be able to cut the time/severity down substantially. I also had a fairly deep cut that was not healing well despite topical antibacterials, and after two days of topical application of Oregano was much better. Anecdotal I know, so take it for what it's worth.

It is unfortunate what happened to your friend, I wish him well. It is never wise to ingest any substance, pharmaceutical or natural without first doing due diligence, particulary in any sort of cocktail. Never take anybody's word for it without following the money.


I'm sorry to hear about your friend Anderson. Definite proof that we should all be a bit more cautious, and that dosing levels are not something to be ignored!

For now I've put the oregano on hold and grabbed some Cold FX - they actually have human trials done and have shown it to be effective. My current cold, the result of being exposed to my sick roommate and some stupid under-recovery on my part, is moving into my chest, so I'd like to nip it in the bud asap.

I'll post how the Cold FX acute dosing worked in a few days.


Well, I'm sure my friend was using a lot more than that. He was following stuff out of extreme books, not label indications. I also believe that his liver was impaired previously because of assaults from all the other "natural remedies" he had been taking for years, including large amounts of beta-carotene from fresh carrot juice.

I agree with your logic about anti-bacterials. It always amazes me that there are people like my friend, who think that all drugs are horrible and dangerous, including antibiotics, but then get all excited to take herbs that have antibacterial properties. Every day even. Personally, I take probiotics every day, so the last thing I want to do is kill any of those critters I'm paying good money for.

The placebo effect is a large effect and very common. Placebos often get a 50% response rate. But it is hard to replicate the effect or sustain it. So the more times you get the effect, the more likely it is to come from the treatment.

I wouldn't hesitate to use oregano oil as a topical antibiotic on occasion. I just wouldn't use a lot of it on large areas of skin every day, straight or even in a sunscreen. (I use sunscreen every day.) My friend put straight oregano oil on large areas of skin for weeks or months. The treated skin eventually became irritated, then ulcerated. The ulcerated skin then actually became infected. The same thing happened in his mouth, where he was squirting the straight oil in order to get better absorption into the bloodstream. Ironically, he need antibiotics to recover from the skin and mouth infections.

Exactly. And some of the "alternative therapy" authors and practitioners are making a lot of money too. Thank you to you and everyone else on this thread for the good wishes for my friend.


So I got the Cold FX - that shit rocks. My face actually hurt from all the mucous that had apparently built up, but after starting the FX acute dosing protocol, I was clearing my head out every 20 min, some weird coloured shit too. : )

It didn't get rid of the cough though, which has continued to love me long time. The g/f encouraged me to see a doctor to confirm I wasn't getting bronchitis or pneumonia, so I got checked out and am good to go on that count.

I talked to a few other people and decided to try out the oregano oil. Man, talk about pungent. It's pretty harsh stuff, just a drop under the tongue burns a bit, so I've mixed a few drops in a lot of water and gone from there.

Unfortunately, I can't say that it has done anything marvelous, though I am feeling better, even managed a light trip to the gym. I could just be finally getting over my cough though, so the verdict will have to wait until next time my throat starts to itch (there's no way it's making its way into my daily routine). I also picked up some BioK+ to restore my good bacteria, in case the oil went crazy on my intestinal track and cleaned me out.

That's it. Thanks again for all the info guys.


PLEASE avoid oregano oil - especially while drinking alcohol.

Hey man, I took oregano oil for about half a year... Sometimes exceeding the dosage but most importantly to note I would take it after and before binge alcohol drinking. I often wondered why the next day I would look like I was dying. I took it before and after drinking because I naively assumed I was cleansing my body with it. Literally the next day I would look just completely awful pretty much like death just completely unhealthy. Another reason I took it was that I would have perfect skin while taking it - and it gave me a nice glow. Now, 5 or so months after quitting, I am getting constant acne. It`s nothing bad but its annoying as hell. the most I would take is about 30 drops in a day, but 15 drops at a time usually.

My skin is just almost always blemished. Sometimes after drinking I will have huge breakouts... That now has stopped because I stopped drinking for about a month - but I never look 100% good or blemish free which totally sucks because before taking oregano oil,

I bascially curious if I have sustained liver damage. The last blood test I had was while I was in China in may and apparantly my blood test came back normal no signs of liver damage or anything like that... but I feel like there have been some long lasting effects of this oregano oil.

To strenghthen my liver I am now taking milk thistle and turmeric occasionally. Trying to avoid all essential oils.


is regular oregano leaves also toxic? I use dried leaves in a lot of my cooking. Is this a bad move?


I would say this is safe but I am no health expert and have clearly already made the mistake of taking too much oil.

also on another note this thread was supposed to be dedicated to the efficacy of oregano oil when used to treat colds and flus.

I originally heard about oregano oil when I caught the h1n1 virus last year... I took it along with garlic cloves to clear it up.

As for the efficacy of it, I believe it is very effective at killing whatever pathogens might be in your body but it is definitely not safe for long-term use.

In my opinion garlic is much safer and does just as good if not a better job at preventing illness.


I have an interest in oregano also , but for different reasons , Right now i am investigating wormwood extract, The herb Sage has many unique properties, specifically wormwood and mugwort


How does this relate to oregano oil?


Pittbull what are the benefits of these other things you listed? I am very interested.



Apparantly thujone is found in many essential oils too, as well as wormwood.... and absinthe.

Really interesting read though.