Essential oils are concentrated plant substances; consequently they are also very powerful, which means they must be treated with respect. Listed below are some guidelines for safe use of essential oils. Consult a professional before use if you have particular concerns.

1. Always Dilute Essential Oils

Due to the concentration of essential oils, they should always be diluted prior to topical application. Safely diluting essential oils not only protects you from adverse effects, such as irritation, phototoxicity, and sensitization, it also makes your little bottle last longer. Read our article How to Dilute Essential Oils for some specific dilution ratios and dilution instructions.

2. Choose Essential Oils Wisely

In some situations, certain essential oils should be avoided. Take a look at the lists below before deciding on a particular oil:

Phototoxic Essential Oils

Some essential oils are phototoxic when used topically on the skin and exposed to the sun. Signs of phototoxicity are severe redness (sunburn), darkening of skin, edema (swelling), and in some cases, blistering.

Essential oils which can cause phototoxic reactions on the skin are:

  • Angelica
  • Bergamot
  • Grapefruit
  • Lemon
  • Lime
  • Mandarin Leaf
  • Orange (Bitter)
  • Rue

For more information, including safe dilution levels for the phototoxic essential oils, consult this article: Phototoxic Essential Oils.

Pregnancy and Breastfeeding

Pregnant woman need to be especially careful when using essential oils. Follow these general guidelines when using essential oils during pregnancy:

      • Daily use is not recommended.
      • Inhalation/diffusing is preferred over topical use. Steam inhalation is not recommended.
      • If using topically, limit to a 1% dilution.
      • Internal use is not recommended.

Essential Oils to Avoid During Pregnancy

The following essential oils should not be used during pregnancy or breastfeeding:

  • Anise
  • Basil (Lemon)
  • Birch
  • Carrot Seed
  • Cassia
  • Cinnamon Bark
  • Dill Seed
  • Fennel (Bitter, Sweet)
  • Myrrh
  • Myrtle
  • Oregano
  • Rosemary
  • Wintergreen

Learn more about Essential Oil Safety During Pregnancy.

Essential Oils Which Can Thin the Blood

For people on blood thinners, about to have surgery, or prone to bloody noses, there are some essential oils to avoid, because they can thin the blood. The highest risk essential oils are:

  • Birch (Sweet)
  • Garlic
  • Oregano
  • Tarragon
  • Wintergreen

Other essential oils that present a risk are Anise, Cassia, Cinnamon, Clove, and Fennel. For more information and a full list, please read Essential Oils Which Inhibit Blood Clotting.

3. Keep Out of Reach of Children

Essential oils are very potent and must be stored out of the reach of children. Some essential oils should not be used on or around children. Some of these include:

  • Anise
  • Basil (Lemon)
  • Cardamom
  • Cassia
  • Clove (Bud, Leaf, Stem)
  • Eucalyptus
  • Fennel (Bitter, Sweet)
  • Lemongrass
  • Oregano
  • Peppermint
  • Rosemary
  • Wintergreen
  • Ylang Ylang


Learn more about Essential Oils and Children, including a full list of essential oils to avoid using with your little ones.

4. Be Mindful of Shelf Life

Essential oils do have a shelf life. When stored properly, they can last for years. Leaving them in a warm area exposed to sun is the quickest way to shorten shelf life of essential oils. Always tighten the caps on the bottles when not in use, as exposure to oxygen can cause oxidation.

For a list of essential oils to avoid if oxidized, estimated shelf life of popular essential oils, how to tell if your essential oils are oxidized (and what to do when they are), as well as making essential oils last longer, read Shelf Life of Essential Oils.

Learning from experts and following the above guidelines can ensure that you have a pleasant experience with essential oils every time!