Which Essential Oils are Toxic to Dogs?

Essential oils have risen in popularity over the past decade.

They are famed for the power to naturally heal a wide range of conditions, including headaches, autism, acne, psoriasis, cancer, anxiety, and ADHD, among others.

However, as a responsible pet parent, it is your job to make sure that whatever you use at home doesn’t harm your furbaby.

While essential oils have some proven benefits for humans, others are toxic to dogs.

On this post, we’ve rounded up the list of essential oils that might harm your pooch, but before then, let’s understand a few basics about essential oils.

What Are Essential Oils?

In case you don’t know, essential oils are concentrated organic compounds derived from plants.

It is these organic compounds that give each plant a distinctive fragrance and taste.  

The oils (or organic compounds) are often located in the leaves, roots, stems, seeds, and nuts of the plant.

The oils are extracted from the above-mentioned sections of the plant by steam distillation or cold pressing.

In some social circles, essential oils are also referred to as volatile oils because they can move from a liquid to a gaseous state rather quickly.  

That’s why if you open a bottle of essential oil, you will quickly smell an aroma as the molecules of the oil escape the bottle in the form of gases.

Each essential oil contains a unique composition of chemicals, which dictates their fragrance, effects, and rate of absorption in the body.

The chemical makeup of essential oils also varies from one plant to another or within the same plant species.

Besides being utilized for aromatherapy, essential oils are also used to flavor foods and drinks, make herbal remedies and personal care products, and are even added to cleaning products.

Essential Oil Toxicity in Dogs

Dogs have a very powerful sense of smell. While humans have about 6 million olfactory receptors, dogs are estimated to have up to 300 million.

As a result, they are more susceptible to odor particles from essential oils than humans.

The moment you are content with the scent of essential oil from your diffuser, for instance, it could be overwhelming to your dog.

Essential oils also contain a wide range of chemicals, which can have complex biochemical interactions in our bodies and our pet’s bodies as well.

If anything, that’s why essential oils have therapeutic effects.

However, while our bodies can process a variety of chemical compounds, our dogs’ systems are much more limited.

As a result, many essential oils tend to be toxic to dogs because the compounds in them react with enzymes and hormones in dogs, messing up their natural body chemistry.

If exposed in large quantities, therefore, some essential oils will cause a dog to exhibit symptoms such as vomiting, diarrhea, skin irritations, loss of coordination, weakness, drooling, and more.

Essential oils are also hydrophobic in nature, which means that they get absorbed fast into your dog’s body through the mucus membrane and the skin.

From here, they are either excreted unchanged or the liver metabolizes some of the compounds in them before excretion.

So, if you have a dog with liver problems, using essential oils around him can worsen his condition.

Another concern with essential oils revolves around the risk of aspiration pneumonia.

Due to their viscosity, there is the risk of the oils getting into your dog’s lungs not only during ingestion but also due to potential irritation that they may cause to your dog’s gastrointestinal tract.

That’s why inducing vomiting after essential oil poisoning is not recommended.  

Applying essential oils topically on a dog’s skin can also cause skin irritation. This may not only be uncomfortable to your dog but he can also lick it off, causing gastrointestinal upset.

Without your vet’s guidance, it is best to avoid applying essential oils on your dog.

Finally, dogs with underlying health conditions may also be at higher risks when exposed to essential oils, especially if they have respiratory risks, if they are unable to properly metabolize the oils, or if they have broken skins (which can allow fast absorption of essentials oils that are applied topically).

So, What Essential Oils are Toxic to Dogs?

Well, here are the essential oils that may be harmful to your dog:

Quick Summary

Essential Oil	Why It Is Not Safe For Your Dog
Tea Tree Oil	Contains terpenes that are quickly absorbed by the body resulting in a host of symptoms.
Pine	Mild doses can mess with your dog’s gut causing it to be irritated
Sweet Birch	Contains methyl salicylate in toxic amounts
Juniper	Causes a host of digestive issues for canines
Peppermint	Cause irritations when it comes in contact with the skin. Ingestion lead to vomiting and sluggishness
Garlic	Contains thiosulphates and disulfides, two compounds that can negatively affect your dog’s red blood cells.
Pennyroyal	Metabolized by the liver, meaning if ingested in large doses, it can cause liver problems.
Wintergreen	Glycoside contained in this oil produces methylsalicylate, which causes a host of issues in a pup’s gut, kidney, and liver organs
Citrus	If exposed to concentrated amounts, your dog may have a seizure, go into a coma, or worse, die
Anise	The jury is still out on this essential oil
Cinnamon	Exposure can cause vomiting, diarrhea, lowered blood sugar, liver disease, and heart rate fluctuations in dogs.
Clove	Derives its therapeutic properties from polyphenolic compounds, which are bad news for dogs.
Yarrow	Rich in compounds (Glycoalkaloids, Sesquiterpene lactones, and Monoterpenes) that can cause digestive upset in dogs.
Ylang ylang	Has a smell that can be overpowering to your dog
Others	Hyssop, Bitter Almond, Horseradish, Tansy, Mugwort, Mustard, Sassafras, Savory, Boldo, Calamus, Camphor, Terebinth, Thuja, Wormwood, Cassia, Oregano, Thyme, Chenopodium, Goosefoot, Rue, and Santolina.

1. Tea Tree Oil

Tea tree oil, also known as Melaleuca, is perhaps the most toxic essential oil for dogs.

Despite its myriad uses around the home, it is best left alone if you have dogs or cats.

You can get away with exposing your pup to it if it is adequately diluted but concentrated forms can be quite fatal.

Essentially, this oil contains terpenes that are quickly absorbed by the body resulting in a host of symptoms.

If you expose your pup to a small dose of tea tree oil, expect drooling and vomiting.

Else, the symptoms can be life-threatening – seizures, tremors, reduced consciousness, coma, and even death.

2. Pine

Pine oil, derived from the pine trees that originated from Scotland, is a popular essential oil in many homes today.

It is claimed to be a good odor neutralizer, natural disinfectant, and massage oil.

Some people also add it to their cleaning products both for the aroma and its healing properties (including improved blood circulation, reduced swelling, pain alleviation, and antibacterial properties).

Unfortunately, dogs don’t respond too well when exposed to pine oil.

Mild doses can mess with your dog’s gut causing it to be irritated. This can even make your dog to vomit blood.

If the dose is high, the oil can affect the central nervous system and the liver.

3. Sweet Birch

Birch oil was originally used to train dogs to pick up scents.

The story changed when some researchers discovered that it actually contains methyl salicylate in toxic amounts.

When undiluted, this oil can cause your dog to develop seizures, gastrointestinal ulcers, and death.

Other symptoms of birch oil poisoning include lethargy, convulsions, and muscle spasms.

4. Juniper

The Juniper Tree, native to North America, produces berries that are totally safe for dogs.

As a matter of fact, the berries are added to most dog foods as they have been known to treat urinary infections.

However, its roots, needles, and bark are not dog-friendly at all.

The oil causes a host of digestive issues for canines. This makes him exhibit symptoms such as weakness, diarrhea, flatulence, lethargy, vomiting, and weakness.

5. Peppermint

Peppermint may be a great flea repellent but it is not a safe product for dogs.

Just imagine the feeling of being locked in a room with a strong perfume lingering in the air!

That’s the same feeling you may be exposing your dog to when you use peppermint oil near or on him—and probably even worse given that their 300 million olfactory receptors do pick scents faster compared to ours.  

Secondly, when peppermint oil comes in contact with the skin, it can cause irritations.

Ingestion of peppermint oil may also lead to vomiting and sluggishness.

Like other essential oils on this list, diluted peppermint oil is relatively safer.

However, even after exposing your pup to the diluted form, keep a close eye and report any behavioral changes to your vet.

To be safe, avoid using it on toy breeds, puppies, and sick or pregnant dogs.

6. Garlic

Whether used as an essential oil or consumed whole, garlic is toxic to dogs.

This is because it contains thiosulphates and disulfides, two compounds that can negatively affect your dog’s red blood cells.

One of the severe blood conditions that garlic can bring about is anemia. Other symptoms include lethargic behavior, shortness of breath, pale or yellow gums, vomiting, flatulence, and diarrhea.

Garlic’s effects on the blood may linger for a few days without any noticeable symptoms.

This means it can be detrimental if the dog doesn’t get immediate help.

7. Pennyroyal

Pennyroyal belongs to the same family as mint. This means it contains Pulegone, a common substance in insect repellents, mouthwash, and fine fragrances.

Although this compound is safe for human beings, it is quite harmful to dogs.

It is also metabolized by the liver, meaning if ingested in large doses, it can cause liver problems.

Whether your dog has existing liver issues or not, vets recommend keeping pennyroyal away from him altogether.

Symptoms of poisoning include vomiting, convulsions, diarrhea, nose bleeding, coughing up blood, and loss of consciousness.

8. Wintergreen

Wintergreen essential oil is often used as a natural solution for muscle aches and pains.

The glycoside contained in this oil produces methylsalicylate, an aspirin derivative.

People looking for a safer alternative to aspirin prefer using wintergreen.

Pet owners don’t shy from applying it to their dogs or diffusing it around the home.

However, since aspirin is unsurprisingly unsafe around dogs, it goes without saying that wintergreen is toxic as well.

It has been proven to cause a host of issues in a pup’s gut, kidney, and liver organs.

This is true for dogs that are already taking steroid or anti-steroid inflammatory drugs.

Signs of aspirin toxicity in dogs include vomiting, stomach ulcers, and liver or kidney failure.

9. Citrus

Citrus oils are derived from peels of ripe citrus fruits such as lemon, lime, orange, grapefruit, and more. These are used as food flavorings and insect repellents.

Because most tick and flea products have citrus oil, many pet owners assume that it is totally safe around dogs.

Yet, it all boils down to quantity. When diluted and used in small quantities, citrus oils will cause no harm to your dog. The opposite is also true.

If you don’t know the proper dosage to use around your pet, you might want to leave it alone.

Puppies and older dogs are especially sensitive to citrus oils.

If exposed to concentrated amounts, your dog may have a seizure, go into a coma or worse, die.

10. Anise

The safety of this essential oil on dogs often attracts a lot of conflicting information.

Most dogs are crazy about this Mediterranean herb. The herb is believed to have a wide range of health benefits to dogs.

For instance, it is often used to help with digestive issues such as gas and nausea as well as to treat respiratory problems like coughs and congestion.

In fact, some dog owners even sprinkle anise seeds on their dogs’ foods and treats without any issue.

However, anise essential oil is different; some dog owners say it is safe for dogs while others warn that dogs should neither be allowed to ingest anise essential oil nor should it be applied directly to a dog.

Put simply, the jury is still out on this essential oil.

So, to be safe, we suggest that you err on the side of caution and consult your vet before you administer this essential oil to your dog.

11. Cinnamon

Cinnamon essential oil has been widely studied for its effects on blood sugar management, infection control, and other condition, thanks to its potent antibacterial, antifungal, and antioxidant properties.

However, the story is different when it comes to pets. Cinnamon essential oil is toxic to dogs.

Exposure to cinnamon essential oil can cause vomiting, diarrhea, lowered blood sugar, liver disease, and heart rate fluctuations in dogs.

Inhalation of this essential oil can also irritate your dog’s lungs, leading to coughing, sneezing, and breathing difficulties.

12. Clove

Traditionally, clove essential oil has been used to soothe toothache, ease digestive upset, and help respiratory conditions in humans.

What about dogs? Well, without mincing words, this essential oil is a no-go for dogs.

Generally, clove derives its therapeutic properties from polyphenolic compounds, which are bad news for dogs.

Dogs’ systems process these compounds differently compared to humans.

The use of clove oils in dogs can cause digestive upset, skin irritation, and rashes.   

13. Yarrow

In humans, Yarrow essential oil is often used to manage inflammation and pain, especially in relieving headaches and soothing nerve pain.

But in dogs, this therapeutic herb can be dangerous.

It is rich in compounds (Glycoalkaloids, Sesquiterpene lactones, and Monoterpenes) that can cause digestive upset in dogs.

14. Ylang ylang

The final essential oil on this list is Ylang ylang.

If you are looking for an oil that will relax your mind and make you less anxious, this oil fits the bill. It is a miracle of nature from the Pacific Islands.

Unfortunately, Ylang ylang has a smell that can be overpowering to your dog.

With a sense of smell that is thousands more powerful than yours, inhaling this oil can cause breathing problems to your dog.

In addition, contact with this essential oil can lead to skin irritations in dogs.

Some of the signs of Ylang ylang toxicity in dogs include coughing, vomiting, difficulty walking, rash, sneezing, a runny nose, eye discharge, and redness around the mouth and nose.

15. Others

Other essential oils that are commonly listed to be unsafe for dogs include:

• Hyssop

• Bitter Almond

• Horseradish

• Tansy

• Mugwort

• Mustard

•  Sassafras

• Savory

• Boldo

•  Calamus

• Camphor

• Terebinth

•  Thuja

• Wormwood

•  Cassia

• Oregano

• Thyme

• Chenopodium

• Goosefoot

• Rue

• Santolina.

While this list is fairly exhausting, it’s worth mentioning that some of the oils can sometimes be used safely when diluted with carrier oils.

Some are also safe when used in small amounts for medium and large-sized adult dogs.

As always, the best way to ascertain whether a given essential oil is safe for your dog or the best way to use it so that it doesn’t react negatively with your pooch’s system is to consult your vet.

Common Symptoms of Essential Oil Poisoning in Dogs

How can you tell that your canine friend is having a bad reaction to essential oils?

Well, if you suspect that your dog is exposed, stay alert for any changes in his behavior.

Here are some of the most common symptoms to look out for:

• Labored breathing

• Poor coordination or difficulty in walking

• Muscle tremors

• Weakness and fatigue

• Pawling at the mouth and/or face

• Vomiting

• Diarrhea

• Excessive Drooling

• Lethargy

• Burns or redness on his lips, tongue, gums, and skin

• Low body temperature

• Chemical burns, redness of the skin, and irritation (for direct skin exposure)  

There is a significant correlation between a dog’s weight, age, breed, and underlying health condition with the severity of the above symptoms.

The smaller and younger your dog is, for instance, the more severe the symptoms are likely to get. The same is true with dogs with liver diseases.

Irrespective of your dog’s age, weight, or breed, the best thing to do if you notice any of the symptoms is to rush him off to the nearest emergency clinic.

Ways To Prevent Your Dog from Being Exposed To Essential Oil Toxicity 

• Refresh our list of essential oils that may be toxic to dogs.

• Some essential oils may cause irritations when applied topically on your dog. So, if you have to apply essential oil on your dog, opt for expertly formulated brands that incorporate essential oils that are safe for dogs.
  
  
• If your vet gives you a green light to use a particular essential oil, never forget to properly dilute it with carrier oils (coconut oil, olive oil, avocado oil, sunflower oil, etc).  As a guide, 3-6 drops of essential oil should be diluted with about 30ml of carrier oil. Avoid applying essential oil on your dog when it is still 100% potent. If possible, conduct a patch test before you apply the oil to your dog’s body. This is done by applying a dime-sized amount of oil and monitoring the area for 15 minutes. Only continue when your dog appears unphased. It is also recommended to keep your dog’s age in mind when diluting essential oils as smaller dogs tend to be more susceptible to any side effects of the oil.

• Keep all essential oils completely out of reach of your dog—including those that are considered safe—as curious dogs may be tempted to investigate the liquids contained in the oil bottles.

• Like any dog product, closely monitor your dog for abnormal behaviors or symptoms when using essential for the very first time. When still learning about the effects of the essential oils on your dog, it is recommended to go slow, especially with the quantity that you give or apply to your dog.

• Only purchase essential oils from 100% trusted suppliers. Stay away from cheap synthetic oils as they are often the cause of toxicity in dogs.

• If you are diffusing essential oils, do so only for a short time—10-15 minutes—in a well-ventilated room. You should also ensure that your dog has a lot of freedom to move from one room to another so that they can walk away if the scents become overwhelming for them.

• Discontinue using essential oil around your dog immediately you notice symptoms like sneezing, coughing, or change in his normal behaviors.

• Only use essential oils to address ongoing health concerns in your dog and not as a prevention measure.

• Avoid using essential oils with pregnant or nursing mothers, epileptic dogs, and puppies under 10 weeks.

Final Thoughts

Essential oils may be natural but not all of them are safe for your dog.

If you must use the ones on this list, it is a good idea to run it by your vet. Let him/her recommend the right dosage for your pup.

Most importantly, sound judgment is vital when it comes to using essential oils safely on dogs.

The information available on the effects of various essential oils on dogs may differ, so responsible use is important.

And every dog has its unique health needs, so what might have worked for your friend’s dog may not work for your dog.

Image sources: 1, 2, 3