Combining Essential Oils, Meds And CYP450 Enzymes

Timing is everything. I say this because I no sooner posted a video ‘Breaking Down Essential Oils’ when I was asked by a former client / student for my opinions regarding essential oils and the cytochrome P450 enzymes. I say ‘timely’ because even though I didn’t outwardly mention anything about CYP450 in the description box; however, I do address the 3A4 enzyme specifically in the document provided. Notwithstanding, the CYP450 enzymes are my primary focus when integrating essential oils with medications.

On that note, the question received was this: [I’ve read]  ‘that some essential oils can cause problems with the working of CYP450 your view the same on this?’ What a great question! The short answer is yes AND no. As mentioned in the previous paragraph, my concern lies in the way we combine natural remedies with medications. I say this because ALL chemicals, including our very own hormones, influence cytochrome P450 activity, making this claim very misleading. Therefore, I’m providing the following ‘chart’ (courtesy of  )which lists the CYP families and functions. It’s important to note that these activities are in an ideal world, meaning, each of us has our own set of polymorphisms altering these activities. What’s more, activity levels appear to be influenced by gender, ethnicity and even location ……

Family       Function                                  Members                                           Names

CYP1    drug and steroid (especially estrogen) metabolism,benzo[a]pyrene toxification (forming (+)-benzo[]pyrene-7,8-dihydrodiol-9,10-epoxide)      3 subfamilies, 3 genes, 1 pseudogene           CYP1A1, CYP1A2, CYP1B1

CYP2   drug and steroid metabolism   13 subfamilies, 16 genes, 16 pseudogenes  CYP2A6, CYP2A7, CYP2A13, CYP2B6, CYP2C8, CYP2C9, CYP2C18, CYP2C19, CYP2D6, CYP2E1, CYP2F1, CYP2J2, CYP2R1, CYP2S1, CYP2U1, CYP2W1

CYP3   drug and steroid (including testosterone) metabolism1 subfamily, 4 genes, 2 pseudogenes CYP3A4, CYP3A5, CYP3A7, CYP3A43

CYP4   arachidonic acid or fatty acid metabolism  6 subfamilies, 12 genes, 10 pseudogenes CYP4A11, CYP4A22, CYP4B1, CYP4F2, CYP4F3, CYP4F8, CYP4F11, CYP4F12, CYP4F22, CYP4V2, CYP4X1, CYP4Z1

CYP5   thromboxane A2 synthase           1 subfamily, 1 gene              CYP5A1

CYP7   bile acid biosynthesis 7-alpha hydroxylase of steroid nucleus  2 subfamilies, 2 genes CYP7A1, CYP7B1

CYP8   varied                               2 subfamilies, 2 genes   CYP8A1 (prostacyclin synthase), CYP8B1 (bile acid biosynthesis)

CYP11   steroid biosynthesis          2 subfamilies, 3 genes     CYP11A1, CYP11B1, CYP11B2

CYP17   steroid biosynthesis, 17-alpha hydroxylase    1 subfamily, 1 gene      CYP17A1

CYP19   steroid biosynthesis: aromatase synthesizes estrogen   1 subfamily, 1 gene  CYP19A1

CYP20   unknown function                 1 subfamily, 1 gene                CYP20A1

CYP21   steroid biosynthesis       2 subfamilies, 1 gene, 1 pseudogene       CYP21A2

CYP24   vitamin D degradation          1 subfamily, 1 gene                CYP24A1

CYP26   retinoic acid hydroxylase    3 subfamilies, 3 genes   CYP26A1, CYP26B1, CYP26C1

CYP27   varied         3 subfamilies, 3 genes   CYP27A1 (bile acid biosynthesis), CYP27B1 (vitamin D3 1-alpha hydroxylase, activates vitamin D3), CYP27C1 (unknown function)

CYP39   7-alpha hydroxylation of 24-hydroxycholesterol   1 subfamily, 1 gene   CYP39A1

CYP46   cholesterol 24-hydroxylase               1 subfamily, 1 gene                     CYP46A1

CYP51   cholesterol biosynthesis      1 subfamily, 1 gene, 3 pseudogenes   CYP51A1 (lanosterol 14- alpha demethylase)

In my opinion, all any of this reflects is the body's response AND ability to accommodate the organisms needs, making polymorphisms proactive adjustments ... NOT defects …they are simply an answer to our current technology / environment. For the most part, these changes are reversible once conditions improve; however, as evidenced by the increase in health issues, we’rein a chronic state of survival which sends messages demanding the production of oxidative stress. I know, this may be hard to believe, yet, every chemical the body produces has a purpose until it's no longer needed at which time, the body then 'flips a switch or two' in order to supply a more appropriate one. What’s more, everything generated is also broken down for elimination; science has been studying this process for MANY years in order to manufacture medications that actually control enzymatic and receptor function in order to regulate use, metabolism, and elimination. This is a problem because the body / nature ultimately cannot be controlled and will adapt to accommodate the needs of the organism. Not to mention, some of these changes irreversibly alter the actions of various subfamilies. Now add the current recognition of essential oils into the equation, which is based on generalized recommendations; the results depend on the individual. Sometimes we're fortunate; although most times, not so much because regardless of the effects were hoping for, there are other things going on that we're unaware of which gradually turn into new symptoms. You see, some oils also induce or inhibit enzyme activity and when combined with medications that are doing some of the same things, the potential for long-term harm is great. Now I'm not saying that patients aren’t warned about various natural remedies; they definitely receive a list of what not to do which, to me, does nothing but create a greater divide between modern and natural medicine. In all honesty, the two worlds do work together; we just need to know how and what to incorporate.

Take the following list of 14 essential oils:

·         Allspice

·         Bergamot

·         Cardamom

·         Carrot seed

·         Cinnamon leaf  

·         Citronella

·         Clary sage

·         Clove bud

·         Elemi

·         Geranium

·         Ginger

·         Neroli

·         Oregano

·         Vanilla absolute (least potent)

After testing the effects of 60 essential oils on the CYP450 2C9 enzyme, it was discovered that all 14 inhibited enzyme activity by at least 50%. The bold lettered oils have an even stronger effect. Without question, this is a problem when combined with such medications as:


  • fluconazole (antifungal)
  • miconazole (antifungal)
  • amentoflavone (constituent of Ginkgo biloba and St. John’s Wort
  • sulfaphenazole (antibacterial)
  • Valproic acid (anticonvulsant, mood-stabilizing)
  • Apigenin


  • amiodarone (antiarrhythmic)

Unspecified potency

  • antihistamines (H1-receptor antagonists)
    • Cyclizine
    • Promethazine
  • Chloramphenicol
  • fenofibrate (fibrate)
  • flavones
  • flavonols
  • fluvastatin (statin)
  • fluvoxamine (SSRI)
  • isoniazid (in tuberculosis)
  • lovastatin (statin)
  • modafinil
  • phenylbutazone (NSAID)
  • probenecid (uricosuric)
  • sertraline (SSRI)
  • sulfamethoxazole (antibiotic)
  • teniposide (chemotherapeutic)
  • voriconazole (antifungal)
  • zafirlukast (leukotriene antagonist)
  • quercetin (anti-inflammatory)

Knowing this is significant! And to think about the number of people using oregano oil on a regular basis believing it’s helping is frightening  ………

THIS is why essential oils are considered a problem. Now 'it' bears repeating ..... not all essential oil constituents influence enzyme activity. What's more, when used by themselves, without medications, and combined with other oils, there happens to be an unexplainable reaction that compliments the nature of the blend rather than conflict which is the opposite of what we see with medications. Truth be told, scientists have admitted in their findings that they don’t understand how or why this happens which inspires them to explore even more.

That said, all chemicals are messengers … they are the mechanism nature uses to communicate. However, the older we are, the more time is needed to reinform the body and give it a chance to recover | heal | thrive. Therefore, my final answer to whether or not essential oils cause problems with the Cytochrome P450 enzymes is ‘not when mindfully integrated or as a stand-alone remedy that is intentionally paired with the diet’. On the other hand, the potential for problematic and/or harmful interactions is real when haphazardly combined with other remedies; especially medications. In other words, it’s time we understand the nature of essential oils  .. for that matter, all chemicals .....  and learn how to integrate and work our body and nature.