General Safety Guidelines

All our safety information referenced from Robert Tisserand's book "Essential Oil Safety, 2nd Edition" and website  Robert Tisserand is one of the world's leading experts in aromatherapy.  His latest book is the most comprehensive on the market and covers groundbreaking material and information that has never before been published.  The book is also the first to explore possible drug interactions between essential oils and pharmaceuticals.  With over 10,000 references to scientific studies, and two well-studied authors, this is information that can be trusted.  
That being said, some essential oils have had very limited or no research conducted with them that can be used properly in regard to human safety.  Always be very careful and do a diluted patch test when using an essential oil on yourself, or an other, for the first time.

The following general safety guidelines are from, and all links will take you there, where you will find extensive and reliable information on essential oil safety. 

How to Use Essential Oils Safely

General Safety Guidelines

Essential oils can be safely used to enhance well-being and as part of a healthy lifestyle. They are used by millions of people every day, most of them without incident. However, essential oils are powerful substances and can be harmful if not used with due care and diligence. The essential oil in a bottle is 50-100 times more concentrated than in the plant, and safety issues apply to essential oils that may not apply to the whole plant or herbal extract.

There is a lot to know about essential oil safety, and this page only encompasses general safety guidelines.


Topical use and dilution

Do not apply undiluted essential oils to your skin. It’s that simple. The most common adverse reaction, experienced by hundreds, possibly thousands of people every year, is a skin reaction, and the most common cause is using an undiluted essential oil. Generally, the reasons for doing this are either (1) ignorance: no-one told you this wasn’t a good idea, or (2) someone told you that it was a good idea, and that it was safe.

Table with recommended topical percentages

Table with recommended topical percentages

Above is a Table with general guidelines for the dilutions of essential oil that are commonly used in different scenarios. For children, see the chart below under “Children”.

In general there are 20-40 drops of oil to 1mL, so you can safely use 20 drops per mL when diluting smaller preparations.

Some essential oils, such as lemongrass, clove or cinnamon bark, are more likely to cause skin reactions than others. However, people frequently have bad reactions to essential oils that are relatively safe because they are used undiluted (see database). This is not because these essential oils contain impurities. The same companies that tell us genuine essential oils can’t cause adverse reactions are the same brands causing most of the reactions. The simple fact is, dilution and risk are directly linked, and this is a well-known phenomenon in dermatology and toxicology.

If you have an allergic reaction to an essential oil, your immune system has been primed, usually for life, so you might need to avoid that oil indefinitely. Click here for Adverse Reaction Reports featuring allergic contact dermatitis. Irritation is different, does not involve the immune system, and usually happens from improper use. Click here for Adverse Reaction Reports featuring irritant contact dermatitis.


Storage, Sensitization and Oxidation

Sensitization is a process that causes your body to become allergic to certain constituents within essential oils, and can also happen with plants and certain medicines.  This process is generally impossible to reverse.  The most common causes of sensitization are using undiluted essential oils, and using oxidized oil.  Oxidation will occur at higher rates when:

  • Exposed to air(oxygen)
  • Subjected to heat, or rapid temperature changes
  • Not protected from light, especially UV

As oxidation occurs, oils will lose their effectiveness until rendered useless and unsafe.  Always store your essential oils in a cool dark place, and oils with a shorter shelf life such as tea tree and citrus oils, should be kept in in the refrigerator.  Keep lids tightly sealed.  Put oils into a bag/container that will protect from light and rapid temperature changes if you plan to transport them.  If buying larger bottles, consider putting the oils into smaller containers to prevent oxidation during use.  Always store pure essential oils in glass containers, not plastic, to prevent them from dissolving and absorbing harmful chemicals.  Diluted essential oils can be stored in plastic.


Shelf Life

The general rule of thumb is as follows:

1-2 years - Citrus fruit, neroli, lemongrass, frankincense, tea tree, pine and spruce oils

2-3 years - Virtually every other essential oil

4-8 years - Sandalwood, vetiver, patchouli

This is the general amount of time you have to use an oil before it becomes oxidized, and therefore less effective and more dangerous with regards to skin reactions and sensitization.  Follow storage suggestions above to increase shelf life of your oils.  See product pages for specific shelf life estimations.  


Bathing with Essential Oils

bathtimePerhaps even more important, do not put drops of essential oil into a bath and then step into it. Essential oils do not mix with water, they float in tiny droplets on the surface, and you are about to sit on those droplets of undiluted essential oil. Whenever essential oils are ‘mixed’ with water without a dispersing agent, there is a risk of irritation, since undiluted droplets of essential oil attach to the skin, often in sensitive areas. Because the oils are warmed up by the water, and also cannot evaporate, they often sting like crazy. Click here for Adverse Reaction Reports featuring bath and washing products.  Therefore, essential oils should first be dispersed in a vegetable oil, or emulsified into an aqueous medium by use of an emulsifying agent. Full-fat milk helps to disperse essential oils in this way. However the dispersion is not complete, so this is not a perfect solution for anyone who might be sensitive, such as children or those with a skin disease.

Undiluted essential oils should not be dripped into the ears, but diluted essential oils may be placed on a cotton wad for partial insertion.

Do not drip undiluted essential oils into eyes as this will cause a chemical burn and may result in temporary blindness. Diluted essential oils may be used close to the eyes. More here.


Oral ingestion

Do not ingest essential oils unless advised to do so by a practitioner who is qualified/licensed to prescribe essential oils in this way. Taking essential oils orally engages many areas of risk that other modes do not. Do not take essential oils either undiluted or in water, as there is a risk of mouth/stomach irritation. This is similar to what happens in a bath (see above) except that mucous membrane tissue is more sensitive than skin, yet our gut only sends out pain signals when erosion has progressed quite far. Essential oils are widely used in food flavorings, and GRAS status for many essential oils applies to food flavoring use, but it specifically excludes medicinal use. One or two drops of most essential oil can be safely taken in a day, but more than this is not recommended.


Inhalation and diffusion

It is not advisable to directly and intensively inhale essential oils for longer than 15-20 minutes, such as with steam inhalation. However, this does not apply to ambient inhalation from essential oils vaporized into the air. If you are diffusing essential oils, it makes more sense to do this intermittently than constantly, all day long. Ideally, diffuse essential oils for 30-60 minutes on, then 30-60 minutes off. This is not only safer, but it’s also more effective as both our bodies and our nervous system habituate to essential oils after this period of time. Whenever you are using or diffusing essential oils, some air exchange (fresh air) is advisable. 

Although perfumes have been known to exacerbate asthma, this has never been recorded for an essential oil. However, anecdotal accounts suggest that individuals with asthma may find that certain essential oils trigger an attack.

Naked flames
Essential oils are flammable, and should not be used in any way that involves close proximity to a naked flame or similar fire hazard. Essential oils are not explosive, and they are safe when used in a diffuser, but there is some degree of risk. Burners that are lit with a candle flame are not recommended, but fragrant candles are safe.



Keep essential oils in a place where young children cannot reach them, and never let them handle essential oils bottles. Even two-year old kids have been known to unscrew caps on essential oil bottles and drink the contents. The fact that the bottle contains an orifice reducer helps a little, but young children are used to sucking liquids. This usually results in a visit to the emergency room. While the end result is rarely fatal, every year there are some very close calls. To help prevent such accidents, all essential oils should be sold in bottles with child-proof caps. Of course this doesn’t always work, but it does make a difference.

Recommended dilution ranges according to age groups

Recommended dilution ranges according to age groups

Above is an age-related Table for recommended dilutions. For the three younger age groups (up to age 6) this applies to any topical application. For the older two age groups (6 to adult) the percentages are for full-body applications. More concentrated dilutions can be used for local applications (small areas of skin).



If you have a skin condition, are pregnant, have epilepsy or asthma, are on a course of treatment with prescribed medication, or are in any doubt about any condition you may have, you are advised to seek the advice of a doctor or suitable practitioner before using pure essential oils.


For educational purposes only. This information has not been evaluated by the Food and Drug Administration.
This information is not intended to diagnose, treat, cure, or prevent any disease.