Cannabis Science Watch

Safety and Effectiveness of a CBD Supplement in Dogs with Osteoarthritis

by Christine H of Help for Fido

Despite their lack of psychoactive effect, strict limits have been imposed on federal funding of, and subsequent research in, virtually all aspects of cannabidiol (CBD) compounds because of their classification as Schedule 1 drugs.

Most information on safety and efficacy for a wide range of health issues comes from individual anecdotal reports being shared increasingly on social media.

As people experience the benefits of these products, it follows that they may also benefit their faithful companions. CBD products are often chosen in place of medications in humans and their pets, including non-steroidal anti-inflammatory drugs (NSAIDs) in an effort to achieve symptom relief. They appear to have fewer side effects often associated with long-term use of NSAIDs.

Cornell School of Veterinary Science and Colorado State University recently examined the potential role of CBD supplements in dogs. The goal of this July 2018 study was to evaluate how a specific proprietary CBD product affects dogs in three ways:

1. What happens to the CBD once it is consumed, in terms of how the dogs react, and are there are any changes in baseline blood chemistries in a small group of dogs?
2. Is CBD safe to give to dogs with documented osteoarthritis?
3. Does CBD administration result in any clinical benefit?

The study used a CBD oil produced by ElleVet Sciences of Portland, Maine. It was made using a proprietary hemp strain that utilized ethanol and heat extraction and then was reconstituted into an olive oil base. It contained less than 0.3% THC.

For the first phase of the study, the researchers looked at two different doses of CBD to see whether the larger dose had a different, possibly harmful, effect on a small group of healthy dogs. The doses were 2 mg/kg (approximately 1 mg/lb), followed two weeks later with 8 mg/kg (approximately 4 mg/lb). Each dose was given once. Evaluations of the dogs’ behavior and baseline blood chemistries (glucose, electrolytes, liver and kidney markers) were conducted regularly over 24 hours following administration of each dose.

The researchers found that both doses had similar effects once consumed: They peaked in the blood between 1.5 and 2 hours following administration, and half of both doses left the blood at the same time, about four hours following administration. No adverse reactions were noted, and no psychoactive effects were observed in any of the dogs.

The second and third phases of the study used a different group of dogs, all of whom had been diagnosed with osteoarthritis but had no other medical diagnoses. Most of the dogs in the study were receiving NSAIDs as part of their treatment for pain.

This group of dogs received 2 mg/kg of CBD oil or a placebo every twelve hours for a period of four weeks. Following a two-week “washout period,” the CBD and placebo treatments were switched. Neither the researchers nor the dogs’ owners were aware of which one they were given during each four-week study period. A veterinarian scored each dog’s pain and activity at baseline, two and four weeks during each study period. Blood chemistries to monitor physiological response were conducted at the same time.

Using well-documented scoring methods, the researchers found that dogs showed a significant decrease in pain and an increase in activity at two and four weeks when they received the CBD oil vs. baseline, and when compared to the placebo. Blood results were not different at any time, with one exception: alkaline phosphatase (ALP), an enzyme found throughout the body, increased over time when CBD was given, in half of the dogs studied. Other abnormal lab findings were related to increased age or use of NSAIDs.

This study sought to determine whether a particular proprietary CBD oil product is safe and effective to use in dogs with pain and limited mobility from osteoarthritis. Despite the small sample size, the design of the study was rigorous, allowing the following conclusions regarding the proprietary product used:

1. Doses of CBD oil as high as 8 mg/kg react similarly and with no observed side effects once ingested by dogs.
2. Doses of 2 mg/kg every twelve hours do not result in adverse behavior or bloodwork.
3. The use of CBD oil results in significant improvement in pain and activity levels in dogs with osteoarthritis.

Since the product used is proprietary, the results should not be assumed to be the same for other products. However, it appears from this study that CBD oil can be used safely and effectively in dogs with osteoarthritis at a dose often cited in social media posts. For some dog owners, this presents another option in place of, or in conjunction with, NSAID use. NSAIDs can have adverse effects on gastrointestinal and kidney systems, especially when used for long periods of time, as with older dogs with arthritis.

The researchers also point out that, based on their findings, CBD oil should be administered at least twice per day and with food for optimal effect. This differs from the typical suggestion that CBD oil works best on an empty stomach.

The finding that 8 mg/kg does not result in any behavioral or laboratory abnormalities may be helpful information for those dogs who need a higher dose to be effective for pain. However, this part of the study examined the effects of a single dose and not of longer-term use.

Since alkaline phosphatase levels increased over time on 2 mg/kg in this relatively brief study, it would be in a dog’s best interest to monitor lab work periodically, especially for liver enzymes including ALP, if they are to receive CBD oil for any length of time.

Overall, this is a very encouraging study and appears to support the growing anecdotal reports. Hopefully, the results will spur other studies using different cannabis strains and combinations of compounds for use in maintaining optimal health for our beloved pets.