Essential Oils and Possible Interactions with Prescription Drugs

Possible Drug Interactions

There are always concerns when you take prescription drugs. 
You never want to do anything that will counteract or interact with your medications. 

According to Shirley & Len Price, "essential oils are known to be active: they gain access to cells by virtue of being fat soluble and are metabolized by the body. As active agents they may react with other drugs present in the body, although there has been no evidence so far that would imply any significant adverse reaction, and essential oils have been used together with allopathic drugs successfully in hospitals."

Essentials oils have the ability to "reduce the drug's effectiveness, or it could enhance it. The degree of change depends on the amount of essential oil used, the percentage strength, and the method of use" (Buckle 85). Some medications are only effected if you take the essential oil orally while others can be effected orally or topically. 

Some essential oils will interact with the creation of specific liver enzymes. Lemongrass, lemon myrtle, and lemon-scented tea tree are examples of oils that could potentially interact with key liver enzymes. These enzymes are vital for "clearance of lipid-soluble drugs by making them more water-soluble, so that they can be safely excreted via the kidneys" (Buckle 85). This means that using specific oils could slow the process time that your body needs to rid itself of the prescription. 

Overall ingestion of certain oils should be avoided altogether. Although many believe that any oil may be ingested, there is plenty of research that suggests otherwise. For example, German chamomile should never be ingested while on medications because negative interactions have occurred (Purchon 46). German chamomile should also be used with caution topically. It could potentially interact with any of the following types of medication: analgesics, anti arrhythmic, antipsychotic, antidepressants (Purchon 47). 

There are always questions about whether it is safe to use grapefruit essential oil with certain medications. Grapefruit essential oil is cold-pressed from the rind.  Any concerns with medication comes from the JUICE of the fruit. Grapefruit essential oil is "safe to use in aromatherapy for individuals who would need to avoid grapefruit juice" (Purchon 63)

We have seen people use both allopathic drugs and oils together without any adverse effects; but we do not have any personal experience in this area. In almost all cases the user has been able to slowly back off of the allopathic drugs they have been using.  Selah Essential Oils can only recommend that the decision to use both together lies solely with the discretion of the user and suggest that you consult your physician for expert guidance. 

Because there is little research to solidify the idea of interactions, it is important to be cautious. Selah always recommends that you consult your physician regarding any use of essential oils while on prescription drugs. 

The chart below has information about types of medication and the oils that could interact with them. Please study this chart. 

Acetaminophen  (depletes glutathione)	Pennyroyal may further glutathione depletion
Analgesic	Clove, German Chamomile, Lemongrass, Melissa, Palmarosa, Blue Tansy (Some)
Anesthesia	Rosemary, Eucalyptus, Ravintsara, and Bay Laurel - high in 1,8 cineole, can interfere with metabolism of anesthesia. Clinical aromatherapists suggest to avoid topically and via inhalation for at least a week prior to any surgeries to prevent complications. Clove, Melissa, Palmarosa
Antiarrhythmic	Blue Tansy, German Chamomile
Anticoagulant medication (Warfarin, Coumadin, aspirin, and Heparin or people with clotting or bleeding disorders, major surgery, childbirth, peptic ulcer or hemophilia)	Eugenol found in Clove, Thyme ct thymol and Oregano should be avoided orally. Birch and Wintergreen should be avoided topically and orally. Patchouli (orally) Lavandin
Anticonvulsants	Clove, Lemongrass, Melissa, Palmarosa
Antidepressants MAOI or SSRI such as Quinidine, Floxetine, and Paroxetine, Codeine, and Tamoxifen	Topically and Orally Clove (bud, leaf and stem) and Nutmeg should be avoided due to possible blood pressure changes, tremors, confusion. Avoid Holy Basil, Bay (West Indian), Blue Tansy, Cinnamon Leaf, Melissa, Palmarosa and Parsley Seed. Oils that contain farnesene and alpha-bisabolol: Balsam Poplar, German Chamomile, Blue Tansy, and Yarrow could possibly interact with these drugs.
Antidepressants (Bupropion)	Citral: Lemongrass, May Chang, Honey Myrtle, Melissa, Palmarosa and Lemon Myrtle should be avoided Blue Tansy
Anti-diabetic medications	Citral: Lemongrass, May Chang, Honey Myrtle, and Lemon Myrtle should be not be taken internally. The following oils could influence blood sugar levels: Anise, Star Anise, Cassia, Cinnamon Bark, Dill, Fennel, Geranium, Lemongrass, May Chang, Melissa, Myrtle, Lemon Myrtle, Oregano, Savory and Turmeric.
Antipsychotic	Blue Tansy, German Chamomile
Aspirin sensitivity	Birch and Wintergreen contain methyl salicylate which is the main component in aspirin.  Some children with ADD and ADHD are sensitive to salicylate. Oils that may exacerbate blood thinning: Anise, Star Anise, Cassia, Cinnamon Bark, Cinnamon Leaf, Clove (bud, stem, leaf), Cornmint, Fennel, Garlic, Lavandin, Marigold, Myrtle, Onion, Oregano, Patchouli, Ravensara Bark, Savory, Tarragon, Thyme ct borneol, Thyme ct limonene, and Thyme ct thymol/carvacol
Calcium channel blocker (found in high blood pressure medications)	Peppermint is a calcium channel blocker and may alter the effect of the medication if taken orally.
Chemo-therapeutic  drugs	Clove, Melissa, Palmarosa
Diuretic medication	Anise has constituents that could counteract this medicine.
Ephedrine (Diet drug)	Avoid Clove and Nutmeg which contain eugenol and could cause cardiovascular changes.
Estrogen receptor  antagonist	Clove, Melissa, Palmarosa
Liver and/or kidney impairment	This could make you more sensitive to the toxic effects from overusing oils. Clove, Thyme ct thymol and West Indian Bay oil could cause interactions with medications for renal disease.
Reverse transcriptase  inhibitors	Clove, Melissa, Palmarosa
Sedatives (Barbituates, benzodiazepines, and anesthetics)	Oils that have sedating properties could interact when applied topically or taken internally.
Stimulants	Clove, Melissa, Palmarosa
Transdermal drugs (Skin patches)	Lemongrass  Do not apply oils to the area where you have applied the patch. It could alter the dosage of the drugs.

Buckle, Jane PhD ,RN. Clinical Aromatherapy: Essential Oils in Healthcare. (2015). page 85.
Price, Len; Price, Shirley (2011-11-11), Aromatherapy for Health Professionals, Elsevier Health Sciences UK, page 71.
Purchon, Nerys and Lora Cantele. The Complete Aromatherapy and Essential Oils Handbook For Everyday Wellness. (2014), page 45-47, 51, 63, 76, 84, 92, 94, 111. 
Tisserand, Robert; Young, Rodney, Essential Oil Safety: A Guide for Health Care Professionals, Elsevier Health Sciences UK 2nd Edition 2014, page 57-59.
Harris, Rhiannon. "Drug-Essential Oil Interactions: Risks and Reassurances," Presentation to Alliance of International Aromatherapists, (17 Dec. 2008), Denver, CO.