CBD vs THC for Dogs

Posted by Nicole Wanner, D.V.M. on

bulldog sits in front of Cannabis leaves

The popularity of medical marijuana is rising in the United States, leading many dog owners to ask: could it help my dog?

Getting a straight answer online can be challenging. State-by-state legal snafus and wordy terminology add to the confusion. They also conceal an essential fact: THC is generally considered unsafe for pets.

You may ask, "if medical cannabis and CBD are so popular, what's the issue with THC for dogs? What are the main differences between THC and CBD?" We'll answer these questions and more below.

What Is the Cannabis Plant?

Before diving in on THC and CBD for dogs, getting acquainted with the "terms of the trade" is helpful. It won't be too painful, we promise!

Generally, 'cannabis' is the scientific name for a small family of flowering plants, including Cannabis sativa and Cannabis indica. People grow thousands of varieties of these plants. They each contain different amounts of natural chemicals called cannabinoids. 

Tetrahydrocannabinol (THC) and cannabidiol (CBD) are the two most well-known cannabinoids. THC causes psychoactive effects (a 'high'), while CBD does not.

In the body, cannabinoids from plants interact with a network of chemicals and receptors called the endocannabinoid system (ECS). Most animals have an endocannabinoid system (including dogs, cats, and humans). It supports a life-saving state of biological balance called homeostasis and serves other roles in the brain and immune systems.

Cannabis, Marijuana, and The Hemp Plant

Depending on what you read and where, you may see phrases like "medical marijuana," "recreational cannabis," and "CBD from hemp." 

Cannabis, marijuana, and hemp are all terms that refer to a plant in the scientific family (or genus) called Cannabis. However, the words typically have different meanings. Knowing each can help you research THC and CBD more effectively for your dog. Here's how we see the terms used most often:

  • Cannabis usually means plant material with a high concentration of the psychoactive compound THC. This is the cannabinoid that produces a "high." Medical and recreational cannabis tend to have high THC concentrations. Colloquial terms like 'pot' and 'weed' also refer to cannabis.

  • Marijuana generally means the same as cannabis: high-THC plant material or extracts. But, some people prefer to avoid the term. In the early 20th century, politicians used it to vilify the "exotic" plant and promote drug prohibition in the United States (1). The word cannabis was popular before American drug prohibition.

  • Hemp, in contrast, refers to plant material or extracts with more CBD and almost no THC. The 2018 United States Farm Bill legalized growing low-THC hemp, leading to the widespread availability of CBD products (2). 
cbd extraction with a dog's face

What Is THC?

We know that THC and CBD are the major natural compounds in a small family of plants called cannabis or hemp. Cannabis generally refers to high-THC plants, while "hemp" is used for low-THC, high-CBD plants. 

But what is THC doing, exactly? Cannabinoids influence processes throughout the body, but here, we'll focus on the brain.

When inhaled or eaten, THC travels to the brain via the bloodstream. It binds to existing endocannabinoid system receptors on brain cells. Like a skeleton key, THC's shape is "close enough" to the receptor's usual partner to trigger a response.

THC's activation of receptors in the brain leads to psychoactive effects. For humans, these effects include changes in thinking, time sense, memory, and other mental processes.

Safety of THC for Dogs

With many people advocating for high-THC medical cannabis, it's no wonder interest has spread to THC for dogs. After all, pets have the same endocannabinoid systems as humans.

However, veterinarians agree that THC in dogs does more harm than good. In rare cases, it can even be deadly (3).

Most dogs are exposed to THC by eating food made with cannabis-infused butter or oil. While THC is not directly poisonous to dogs, they experience its mental and physical effects more strongly than people. In some cases, the resulting symptoms can be dangerous without medical attention. 

Products with highly-concentrated THC are especially hazardous. Even worse, many THC edibles contain ingredients toxic to dogs such as chocolate, raisins, and the artificial sweetener xylitol. 

Symptoms of THC Poisoning in Dogs

Fortunately, the effects of THC intoxication in dogs are easy to spot. Signs your dog may have consumed THC are:

  • Difficult or uncoordinated walking
  • Decreased responsiveness
  • Drooling
  • Agitation
  • Vomiting
  • Tremors
  • Loss of bladder control
  • Abnormal heart rate or rhythm
  • Seizures

If you believe your dog ate something containing THC, consult your veterinarian immediately. Remember, your vet's only goal is to help your dog. Be honest about your concerns, even if cannabis is illegal where you live. Your openness can save valuable time (and money) when treating your pet.

Luckily, supportive care at your veterinarian's office will get most dogs through exposure to THC. Still, a few dogs have died after eating cannabis products that contain chocolate or high-concentration THC butter. Secure all high-THC items out of reach to keep your best friend safe.

THC with a red X and CBD with a green circle

Differences Between CBD and THC for Dogs

We know that THC and cannabis products can be unsafe for dogs. But what about CBD?

CBD is a cannabinoid like THC, but there are some key differences. Most importantly, CBD does not have psychoactive effectsUnlike THC, CBD does not act like a "skeleton key" to control the endocannabinoid system.

It interacts with the brain's endocannabinoid system less directly, leaving memory, coordination, and bodily functions intact. CBD also influences other receptors in the body.

One example is TRPV1, a receptor involved in inflammatory pain. Researchers are studying how CBD interacts with the TRPV1 receptor as a potential method of pain relief in inflammatory conditions (4).

A not-so-fun fact: TRPV1 is also responsible for the burning spiciness of capsaicin, a compound found in hot chili peppers (5). 

Safety of CBD in Dogs

Fortunately, research indicates that high-quality CBD is well-tolerated in healthy dogs (6). The side effects of CBD in dogs are generally mild, and it's unlikely dangerous to give a dog more CBD than their usual dose. 

Remember, CBD products may be unsafe for your dog if they contain toxins like chocolate or xylitol. Additionally, low-quality CBD may contain impurities, so look for independent, third-party laboratory analysis with a certificate of analysis when shopping. This information will confirm that your dog's CBD is the correct strength and free of THC, pesticides, or other contaminants.

Side effects of CBD in dogs to watch for include:

  • Drowsiness
  • Reduced activity
  • Diarrhea
  • Changes in blood pressure
  • Changes in liver function
  • Interference with prescription medications

You'll notice that the last three side effects on our list are impossible to spot just watching your dog at home. Because of this issue, your dog's CBD regimen should always be a team effort with your veterinarian (7).

Some dogs may not tolerate CBD well, especially those with heart or liver problems (8). Or, your dog might benefit from a reduced dose and extra monitoring. Your veterinarian is your best ally in making CBD a safe part of your dog's wellness plan.

Lastly, keep in mind that researchers have only begun to investigate CBD for dogs. Several studies show that most healthy dogs tolerate CBD well in the short term, for days, weeks, or a few months. Still, we have less information about the impact of years of CBD use. 

Rest assured, scientists will continue researching CBD's safety and benefits for dogs. More comprehensive details will be available in the future. 

dog licking CBD oil bottle

CBD Products for Dogs

Even after you've consulted your veterinarian, it can still be daunting to research the variety of CBD products available to your pet.

Here are a few common types of pet CBD and their key features:

  • CBD oil: These products are usually given orally using a dropper. CBD gets to the bloodstream after being absorbed through the cheeks and gums. CBD oils include hemp extract mixed with a carrier oil like coconut or MCT oil. If CBD oil upsets your dog's stomach, they may be sensitive to the carrier oil rather than the CBD itself. CBD oil for dogs is generally the best "extra strength" option if your dog is a large breed.

  • Topical CBD: Topicals include balms, lotions, creams, and other CBD products applied to the skin. These formulas usually contain other soothing ingredients, like shea butter. CBD sinks into the skin directly with these products, and very little reaches the bloodstream. Avoid applying CBD and other topicals to damaged skin or wounds without your veterinarian's supervision. The ingredients may sting or delay healing.

  • Edible CBD: Some CBD comes in the form of chews made for your dog to eat. Chews are flavored and may be easier to use if your pup dislikes the taste of CBD oil. Check the nutrition facts, though - calories from chews can add up, especially for small-breed dogs. Keeping your pet at a healthy weight is the best way to support their overall health. Giving chews after a meal can help with CBD absorption (9).

Several hemp extract varieties are also available within each type of CBD product. Hemp extracts come as isolates (CBD only) or full-spectrum, which contains CBD, other cannabinoids, flavonoids, and terpenes. 

THC vs CBD for Dogs: What's The Verdict? 

What have we learned about CBD vs. THC for dogs?

Here are our key takeaways:

  • THC and CBD are both natural chemicals found in the plant family Cannabis. THC is psychoactive (causes a high), while CBD is not.
  • Despite the popularity of medical marijuana in people, THC is unsafe for pets. Know the signs of THC intoxication, and be honest with your veterinarian if you suspect your dog ingested THC.
  • Preliminary studies indicate that most healthy dogs tolerate CBD well. Consult your vet before starting CBD, especially if your dog has pre-existing health concerns. Start with a low dose and build up slowly if needed.
  • Oils, topicals, and edibles are different formulations of CBD for dogs. Which is best for your pet depends on dosage, body size, your pet's health concerns, and other factors.

Ultimately, choosing the right CBD formula depends on your dog's unique needs. Talk with your veterinarian to develop a wellness plan that supports your dog's long-term health.


  1. https://origins.osu.edu/article/illegalization-marijuana-brief-history?language_content_entity=en

  2. https://nationalaglawcenter.org/wp-content/uploads//assets/articles/essman_hemp.pdf

  3. https://pubmed.ncbi.nlm.nih.gov/23216842/

  4. https://bpspubs.onlinelibrary.wiley.com/doi/full/10.1038/sj.bjp.0705920

  5. https://journals.lww.com/clinicalpain/FullText/2008/02000/Capsaicin__TRPV1_Agonist__Therapy_for_Pain_Relief_.9.aspx?casa_token=Y11pJipDC9YAAAAA:0BA8ECSj5kiSaYk-ry2x6sBFujm7wRgT8gApx1s5KbzSPdc_0uczhvSiwfp9O-NLPqwSsmIbEaNMEegtSHPsiBs

  6. https://avmajournals.avma.org/view/journals/ajvr/82/5/ajvr.82.5.405.xml?tab_body=fulltext

  7. https://lolahemp.com/blogs/news/cbd-oil-for-your-dog-everything-you-need-to-know

  8. https://www.frontiersin.org/articles/10.3389/fvets.2018.00165/full?fbclid=IwAR1S16ZSa-DktbvZ1wHFczaD_JV8Eg8mjQqtlNJi8Z0t0xpBGskl2J364no

  9. https://www.frontiersin.org/articles/10.3389/fvets.2018.00165/full?fbclid=IwAR1S16ZSa-DktbvZ1wHFczaD_JV8Eg8mjQqtlNJi8Z0t0xpBGskl2J364no

← Older Post

Leave a comment


Dr. Nicole Wanner graduated from the University of Minnesota College of Veterinary Medicine in 2018. Currently, she is an academic research veterinarian studying CBD and DNA. Her research has been published in trusted international research journals. Dr. Wanner is passionate about pet wellness and has professional interests in genetics, behavior, and healthy aging. In her free time, she enjoys hiking and reading sci-fi novels. She shares her home with her husband Evan and their two mischievous rescue cats, Sylvie and Nemo.
RuffRuff App RuffRuff App by Tsun