Do's and Don'ts of Essential Oils - A Guide

Posted by Monika Meulman on

A quick and easy guide about using essential oils safely from The Healing Muse at our Healing Muse Apothecary.

We’ll go over topics like expiry, preparations, whether or not you can safely ingest essential oils, and photo-toxicity. We emphasize the importance of doing your own research before using essential oils and always cross-examining your sources.


First off, let’s talk about expiry dates.

Some people say that essential oils do not expire and that they are good forever…

This is misinformation.

Essential oils oxidize, they change as soon as the vials or small containers open and oxygen gets into the container. The oxygen immediately starts changing the integrity and the strength of the essential oil, and weakening its structure. Although you will seldom see an “expiry date” as you would on traditional food items, essential oils do break down.

Here’s a general guideline for how quickly your oils breakdown.

citrus essential oils

Citrus oils 

(sweet orange, bergamot, grapefruit, lime, lemon, etc.) tend to break down within 6 months. They will last about 6 months at full integrity from the time of bottling or preparation and then they will start to break down in quality very quickly. Within one year, citrus oils are pretty much useless. They are definitely the most volatile oils out there so you’ll want to purchase them in small quantities, or, use them very quickly if you’re purchasing them in larger quantities.

Robert Tisserand has a great summary of citrus oil — keeping your oils ‘on ice’ in a write up here.

Citrus fruit oils are high in limonene, and limonene is especially prone to oxidation…When lemongrass oil was intentionally oxidized, it lost almost all of its antibacterial activity.

Robert Tisserand – Tisserand Org

Pro Tip: 

If you use your essential oils everyday, purchase small quantities that are used up quickly, or use a smaller container for daily use and place the larger container in the fridge.


herbal essential oils

Herbals, or green oils 

(Lavender, Thyme, Oregano, Sweet Fennel, Rosemary, Marjoram, Basil, etc.) will be good for 1-2 years from the time of bottling. They will stay fairly strong and concentrated for this time. This does not mean they’re not still oxidizing – they are. They just keep their strength and integrity for a longer period of time.



heavy essential oils

Heavy oils

(resins like Benzoin, Patchouli, Labdanum, etc.) actually get better with age and they can be good for 5-7 years. Some heavy oils will thicken up and become almost inert, and that makes them very wonderful for blending into perfumes, and making aromatic blends, because they will keep for longer. They might not have the exact same therapeutic properties after 7-10 years but the aroma becomes stronger and more concentrated, so they’re a much more luxurious and decadent aromatic to use for blending.

I have for some time now been tempted to buy a few litres of patchouli and keep it in reserve for say 10 years…What that means is that for most perfumery purposes - aged, dark patchouli would be less saleable, than for example a light patchouli. On the other hand for aromatherapy purposes it would probably be more highly sought after (I say probably because that’s not really my area of expertise, but from what I hear dark is preferred).

Basenotes web – perfume forum

I have a 10-year-old Patchouli oil and the aroma is divine!

Save old resins for beautiful unique resin based perfumes.

Inert, thick resins can be gently warmed in a double boiler or bowl of hot water



Next, I’d like to touch upon the concept of ingesting essential oils...

As a long time professional member of the CFA – Canadian Federation of Aromatherapy, I recommend the safety guidelines provided by our national organiztion:

The CFA does NOT recommend nor condone:

the topical application of undiluted essential oils

the ingestion of any essential oil in any manner

CFACANADA.COM – safety notice

A lot of people like to come into the Apothecary and say “Oh Monika, do you have the essential oils that I can ingest?” and my answer is always “No”.

There is no such thing as an essential oil you can ingest safely.

There is no therapeutic grade, farm grade, organic grade, specialty grade, centigrade, or whatever other grades you’d wish to talk about – that you can safely ingest.

Essential oils are not to be ingested unless they’re diluted properly into something like a lipid or a fatty substance, as they can only dissolve in fats. Furthermore, when they are properly diluted, ideally they will also be mixed and put into a capsule, never directly into our mouths or throats through a glass of water or tea.

Do not ever put a drop of essential oil into water and think that it will in any way blend and be usable as an aromatic water. Essential oils float on the surface of the water and do not blend in with the water. They need a fatty agent to disperse and blend them in properly. If you were to drink a glass of water or any water based liquid blend with a few drops of essential oils added to it, the essential oils would not mix with the water. What happens is, first, they will coat the inside of your mouth, gums, throat, esophagus, and stomach lining and they could possibly burn these very sensitive tissues of your body. You are gaining no benefit, no benefit at all whatsoever from the essential oils in that drink.

can I ingest essential oils? 

Essential oils are high irritants to our mucous membranes

So, any time someone says that you can take essential oils internally in a glass of any liquid, please remember that is not the case. This is an ineffective and harmful way of using essential oils. It may smell good, but I promise there are much better ways of using essential oils in your day-to-day life.


Lastly, I would like to touch on certain chemistry related aspects of essential oils, specifically, photo-toxicity, and photosensitivity, that some people don’t take into consideration.

citrus oil phototoxicitySome essential oils make our skin prone to burning in the sun. 

Essential oils that are in the citrus family tend to make our skin photosensitive. This means they decrease the amount of time that you would need to spend outdoors before you get a sunburn. This is something that is extremely important to know, in my opinion.

If you were to make your own body cream or lotion to use outdoors in the sun, or first thing in the morning in the summertime, you would not use an essential oil in the citrus family because they would cause your skin to be more prone to burning.

essential oil phototoxicity

An after sun moisturizer? Maybe, sure. You can make an after sun serum, body oil, cream, or Aloe Vera gel, and you can add citrus to that at the end of the day or in the evening – perfect. That might very well be quite refreshing and soothing, but this should never be used during the day for sun time.

There are some oils like Bergamot that have bergaptene removed. Bergaptene interacts with UV rays to produce chemical burns and skin discoloration, this is the component that would make it photo-toxic. Once that component has been removed, it makes the oil safe to use in the sun. However, there are so many safe oils to use that aren’t citrus related that make beautiful skin care for the day time in summer, that I don’t think you need to be stuck on citrus oils at all. Keep your citrus oils for the evening, refreshing room sprays, perfumes AFTER being outdoors. Save them for special occasions that don’t involve being outdoors in the direct sunlight.

Oils that are great for sunny days: Rosewood, Geranium, Sandalwood.
A beautiful evening time skin cooler: Lemon & Peppermint essential oils in an Aloe Vera gel.

We hope you enjoyed this quick, do’s and don’ts guide of essential oil and aromatherapy safety. Hopefully this encourages you to stop and think, be more mindful and careful of the essential oils you’re using, and to never forget to investigate and cross reference the information you hear and read.

Please leave us any questions in the comments below and we would be happy to help keep this conversation going.

Find us on YouTube for the full video:

Share this post

← Older Post Newer Post →


Leave a comment

Please note, comments must be approved before they are published.