Essential Oils and Dogs: Are they safe and effective?

Pet care & safety

Last month I saw this adorable labradoodle named M (yes, just M). He was only three weeks old, which is why his owner was using the highest quality essential oils in his all-natural puppy shampoo and treating him to a pure rosemary oil rub-down afterwards to keep fleas and ticks at bay.

As she explained her regimen, she gushed over the brilliant state of his coat, which looked to me more like a greaser’s shiny hairdo than a dog’s. Cute, to be sure, but I had to ask: Are these essential oil baths effective? Are essential oils safe for dogs when applied like that? Are some oils acceptable and others not?

Here’s a pet-specific primer for those of you who think of essential oils as an indispensable item in your cosmetic, medicinal, and hygienic cupboard and wonder whether they’ll work just as well on your dog:

What are essential oils?

Essential oils are common aromatic compounds found in nature, primarily in plants, that have a tendency to turn readily from a liquid state to a gas state. This so-called volatility of essential oils is what gives plants the ability to produce an aroma that can attract or repel bacteria, fungi, insects, other animals, and even other plants.

Essential oils, for example, explain why some flowers emit an aroma that attracts honeybees while others produce a nauseating stench. As such, they’re responsible for biological processes as diverse as pollination and reproduction.

How are essential oils used?

For the entire history of humanity, our species has relied on essential oils not just for their attractive aromas, but for their medicinal qualities, too. That which helps plants and animals draw and repulse can also help humans stay clean, prevent disease, and even attain specific emotional states.

Peppermint oil, for example, has been prized for its antibacterial capabilities; frankincense, for its immune-boosting functions; and vetiver for its stress-relieving qualities.

Are essential oils effective?

It’s a question worth asking. Because while the entirety of human history tells us otherwise, few comprehensive studies have confirmed the efficacy of these volatile aromatic compounds.

The studies we routinely perform on humans to ensure efficacy of prescription drugs have been but rarely performed to determine the true efficacy of essential oils. Moreover, when these studies have been undertaken, it appears that human response is highly variable.

While we don’t properly understand why that is, we suspect it has something to do with epigenetics, the study of genetic variations that come from living in a very specific location. That’s probably why some people swear by certain essential oils while others think it’s all hogwash.

Because of this, we have strong suspicions about the efficacy of essential oils but have a hard time proving it in a genetically diverse country like the US, or in regions like the EU (both where funds for these studies are most available).

Given the genetic diversity of dogs, along with the minimal research dollars dedicated to them (relative to humans), the question of efficacy remains difficult to answer definitively. Nonetheless, based on what we do know, it’s likely that at least some essential oils are effective for treating and preventing some conditions.

Are essential oils safe for dogs?

The answer is that almost all essential oils are safe whether they’re diffused into the air at a reasonable distance. However, ingestion is another matter altogether

The use of essential oils for anything beyond aromatherapy is considered controversial in veterinary medicine. Some veterinarians believe that, when ingested, all essential oils are toxic and should never be used, even topically, given the ability of dogs to lick most anything off of themselves. Note that anything used topically should be considered potentially ingested when used on dogs.

Common Essential Oils and Their Uses for Dogs

Most essential oils reportedly offer multiple benefits. Here are some of the most commonly used essential oils and the veterinary benefits:

  • Cedarwood: Used as a bug repellant. It’s also considered calming and supposedly soothes respiratory conditions like kennel cough.

  • Citronella: Most commonly used oil for flying bug repellant. Potentially heartworm-carrying mosquitoes tend to hate it.

  • Chamomile: Famous for its soothing antiseptic properties. Chamomile oil is meant to ward off microbes and reduce inflammation. It’s reported to be calming for the GI tract and nerves too.

  • Fennel: Used in human endocrine medicine to help balance pituitary and thyroid hormones. Some veterinarians believe that fennel oil is effective for similar issues in dogs.

  • Frankincense: Reportedly used to treat bladder cancer in humans, frankincense oil is being implemented in canine tumor treatments too.

  • Lavender: Ahhhh, the lavender aroma. Can you think of something more soothing? Limited studies have shown that lavender oil works to calm dogs, too. One specifically addressed its efficacy for travel anxiety when applied to a bandana around the neck. But it’s not just for calming. It reportedly helps treat wounds too.

  • Helichrysum: Used for bleeding issues in dogs who have clotting problems and for those with issues of the circulatory system to prevent bleeding. It’s used to treat some cardiac, nervous system, and skin conditions too.

  • Orange: Primarily used as a deodorizer to vanquish dog smells, especially in stool and urine cleanup. It’s also considered a bug repellant.

Note: Some orange oils have a questionable safety profile. Only the sweet, edible varieties are considered safe.

  • Peppermint: Prized for its energizing properties, peppermint oil is also widely used to prevent fleas.

  • Rosemary: Another bug repellant, rosemary oil is also used for skin-related concerns.

  • Spearmint: As in humans, it’s Primarily used for dogs as a gastrointestinal soother. Nausea is considered nemesis to spearmint oil

Other Commonly-used Essential Oils for Dogs

  • Angelica Root

  • Basil

  • Bergamot

  • Black Pepper

  • Cajeput

  • Caraway

  • Cardamom

  • Carrot Seed

  • Cinnamon

  • Cistus

  • Coriander

  • Cypress

  • Valerian

  • Elemi

  • Eucalyptus

  • Geranium

  • Ginger

  • Grapefruit

  • Lemon

  • Lemongrass

  • Mandarin

  • Marjoram

  • Melissa

  • Myrrh

  • Neroli

  • Vetiver

  • Niaouli

  • Nutmeg

  • Opopanax

  • Palmarosa

  • Patchouli

  • Petitgrain

  • Plai

  • Rosalina

  • Rose

  • Sandalwood

  • Spikenard

  • Tangerine

  • Ylang Ylang 

Essential Oils That Are Dangerous to Dogs

  • Anise

  • Birch

  • Bitter Almond

  • Boldo

  • Calamus

  • Camphor

  • Cassia

  • Chenopodium

  • Cloves

  • Garlic

  • Goosefoot

  • Horseradish

  • Hyssop (most varieties)

  • Juniper

  • Mugwort

  • Mustard

  • Oregano

  • Pennyroyal

  • Pine

  • Red or White Thyme

  • Rue

  • Sassafras

  • Santolina

  • Tansy

  • Tea Tree

  • Terebinth

  • Thuja

  • Wintergreen

  • Wormwood

  • Yarrow

Signs of Essential Oil Toxicity in Dogs

Poisoning by essential oils can manifest in many ways. According to the ASPCA’s Poison Control,

“The most common clinical signs with dermal exposure seen by APCC include ataxia, muscle weakness, depression, and behavior changes. In severe cases, hypothermia and collapse may occur. With oral exposure, vomiting, diarrhea, and central nervous system depression can be seen.

In severe cases, seizures and rarely liver injury has been reported with pennyroyal and melaleuca oils. If inhaled, aspiration pneumonia may occur.”

What makes certain essential oils so toxic to dogs?

The troubling thing about essential oils is that they’re readily absorbed by the skin and mucous membranes. That’s how they enter the body and eventually the bloodstream, where it travels to tissues that may benefit from them.

But once in the bloodstream, as happens with any other non-native chemical, essential oils have to be processed. Potentially, many organ systems can be damaged, but the liver is especially vulnerable in dogs and cats. They simply don’t have the enzymes needed to handle them. And if the liver can’t get rid of a substance, it remains in the bloodstream where it’s free to damage other sensitive tissues.

Are some essential oils more toxic to dogs than others?

Some essential oils are definitely more toxic than others. But toxicity can be individual-specific too, meaning some dogs are more capable of processing these compounds than others. Some dogs also may be uniquely sensitive and we have no way of knowing which dogs will have more trouble than others.

It’s also true that some essential oil preparations contain other ingredients, not just the oil itself. These can be harmful if they’re not canine-friendly.

The Role of Essential Oil Preparation

But aren’t essential oils in almost every shampoo and dog product, you ask? Sure, but it typically comes down to how they’re prepared and their concentrations.

Teensy concentrations of these products, especially when applied topically and rinsed off, don’t get a chance to even enter the bloodstream. Others enter in such low concentrations that the liver might well be capable of handling them.

With dogs that are ill, especially with respiratory illnesses and skin lesions, we have to be extra careful. In these cases, more of the compounds can enter the bloodstream, effectively making them more toxic.

Finally, it’s important to mention that 100% essential oil preparations are now widely available and more popular than ever, which is at least partly responsible for the rise in essential oil toxicity in the US. These preparations should never be used in their un-diluted form, even in a diffuser.

How can I use essential oils safely around my dog?

Here are some simple rules to live by when it comes to using essential oils:

  • Do not diffuse essential oils around dogs with respiratory ailments unless you ask your veterinarian first.

  • Never apply essential oils in any concentration directly to a wound or to raw skin.

  • Only use essential oils that are therapeutic-grade and produced by a respected company.

  • Consider the smell test. Be conscious of your dog’s reaction to any diffused essential oil. If they’re restless or park themselves as far from the diffuser as possible, don’t force it on them.

And finally, always ask your veterinarian before using essential oils. Offering ingestible or topical essential oils in anything but a commercially available consumer dog product that’s been recommended by veterinarians is not a great idea.