Does CBD Calm Aggressive Dogs? What The Largest Study Ever Reveals

Cranky first, calm later: Dogs given CBD had high aggression scores initially, but mellowed out over time.

Dogs receiving CBD supplements showed a notable decline in owner-reported aggressive behaviors over time compared to dogs not given the compound, according to an observational study. The research initiative, put together by the Dog Aging Project, tracked nearly 50,000 companion dogs across the United States.

The finding suggests CBD could play a role in managing canine aggression, though researchers caution that owners may have simultaneously used training or other interventions that contributed to the behavioral changes.

Dogs consistently given CBD for at least two years initially displayed higher-than-average aggression levels compared to dogs never given the supplement. Over time, however, their aggressive behaviors declined at a faster rate. By the end of the study period, these dogs showed below-average aggression compared to their non-CBD counterparts.

“The decline in the intensity of aggressive behaviors suggests the potential use of CBD in dog training,” the researchers wrote in their paper published in Frontiers in Veterinary Science.

CBD Dogs Started More Aggressive But Improved Faster

The study analyzed survey data from 47,355 dogs enrolled in the Dog Aging Project between December 2019 and December 2023. Owners completed annual surveys about their dogs’ behaviors using a modified version of the Canine Behavioral Assessment & Research Questionnaire, which researchers used to create behavior scores based on reactions to various situations including interactions with strangers, other animals, and unfamiliar circumstances.

Among the behaviors tracked, aggression stood out as showing the most significant difference between CBD and non-CBD groups over time. Dogs receiving CBD also showed declining intensity in reactions to unfamiliar circumstances and reactions to other animals, two separate behavioral measures that researchers tracked alongside aggression.

The fact that CBD-using dogs started with higher aggression levels hints that owners may have turned to the supplement specifically to address behavioral issues. Around 5.5% of all dogs in the study received CBD at some frequency, with owners most commonly administering it as a daily supplement.

The behavioral improvements over time raise questions about what exactly drove the changes. CBD might be directly affecting the dogs’ temperament, or the improvements could stem from owners taking multiple steps to address aggression, such as working with trainers or veterinarians.

Previous controlled studies have shown CBD can reduce stress-related behaviors in dogs during separation and car travel. One study found shelter dogs given CBD displayed less aggression toward humans, aligning with the current findings.

Health Problems Remain Primary Reason for CBD Use

Beyond behavior, owners primarily gave CBD to dogs with specific health conditions. Dogs with dementia showed the highest rate of CBD use at 18.2%, followed by those with osteoarthritis at 12.5% and epilepsy at 10.6%.

The study found seven health conditions significantly associated with CBD use: dementia, osteoarthritis, epilepsy, hip dysplasia, cancer, chronic diarrhea, and a group of ongoing digestive problems such as repeated vomiting or constipation. Researchers noted that some of these associations reflect established therapeutic uses, like CBD for epilepsy, while others may simply reflect owner perceptions about CBD’s health benefits.

Interestingly, dogs with gastrointestinal problems and chronic diarrhea were more likely to receive CBD, even though these symptoms can be side effects of CBD supplementation in dogs.

Age and Location Patterns in CBD Use

Dogs receiving CBD frequently (daily or as non-prescription medication) averaged 10.2 years old, while those with infrequent use averaged 8.1 years, compared to 7.6 years for dogs not given the supplement. Male dogs showed slightly higher CBD use rates than females, though researchers couldn’t explain the gender gap.

Geographic patterns revealed how human attitudes toward cannabis influence pet care choices. Dogs in states with legal medical cannabis programs had higher CBD usage rates compared to states without medical cannabis programs. On average, 5.8% of dogs in medical cannabis states received CBD versus 4.7% in states without such programs.

CBD use varied by location, ranging from 1.6% in Iowa to 9.7% in Hawaii. Among breeds, Leonbergers showed the highest CBD use rate at 10.3% for purebreds with more than 50 dogs surveyed.

What This Means for Dog Owners

The research relied entirely on owner-reported data, which introduces potential bias and limits the ability to draw causal conclusions. Owners may have misreported or failed to report CBD use, and the study lacked information about CBD product composition, dosages, and specific formulations.

Researchers emphasized that the behavioral improvements could result from training, other medications, or lifestyle changes owners implemented alongside CBD. Future randomized clinical trials with measurable data like cortisol levels and activity tracking would help establish whether CBD directly causes behavioral changes and identify proper dosing.

The study represents the largest assessment of CBD use in companion animals to date and provides a foundation for understanding how the human-animal bond influences health decisions for both species.

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Disclaimer: This article is for informational purposes only and does not constitute veterinary medical advice. Always consult with a licensed veterinarian before starting, stopping, or changing any supplements or medications for your pet. The observational study discussed cannot prove cause and effect between CBD use and behavioral changes in dogs.

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