By Larry Lamb, DVM

CBD, or cannabidiol, is a compound found in cannabis and hemp. In most cases, CBD does not contain delta-9-tetrahydrocannabinol (THC), the compound that gives marijuana its psychoactive properties. In fact, most CBD products are derived from hemp and not from marijuana.

Veterinarians are beginning to study CBD’s effects on pets and assess its safety. Despite this lack of official guidance, pet owners are increasingly seeking out CBD for their pets. In a survey conducted this year by the Veterinary Information Network, an online community of veterinarians, nearly two-thirds of survey respondents said they were asked about cannabis by their patients. A study from my alma mater,  the Cornell  University College of Veterinary Medicine, found that 2 mg per kilogram of CBD twice daily “can help increase comfort and activity” in dogs with osteoarthritis

Pet owners are turning to CBD to help manage pain, arthritis, seizures and other health problems in their pets. And a growing crop of CBD products marketed for pets—including tinctures, capsules and chew treats—has burst onto the market to meet the consumer demand.

On the federal level, CBD remains categorized by the Drug Enforcement Administration as a Schedule 1 controlled substance, the same as heroin. As of July 2018, 47 states have gotten around this federal restriction by legalizing CBD for human use within their own states. Physicians in those places can now recommend CBD to their patients, and consumers can often buy the compound on their own—for themselves or their pets—without any interaction with a healthcare professional.

Only California has passed legislation that specifically authorizes veterinarians to discuss cannabis with their clients, according to experts. As a result, vets lag behind physicians in working with cannabis and researching its use in pets.

While some pet owners swear by CBD, keep in mind that researchers are just starting to learn how to use it for pets, and at which dosages, says Stephanie McGrath, D.V.M., a veterinarian and assistant professor of neurology at Colorado State University’s College of Veterinary Medicine and Biomedical Sciences.

Because cannabis, especially for pets, is largely unregulated, it can be difficult to know which CBD products have been formulated responsibly, are free from contaminants, and contain the ingredients that the product labels list. When shopping—whether online, in a retail store or a dispensary—look for products that claim to follow Good Manufacturing Practices or that have a seal from the National Animal Supplement Council (NASC). These labels increase the chance that a product has been made with safe ingredients in a clean, high-quality environment. 

For any CBD product for you or your pet, your best bet is to find a company that has commissioned independent third-party testing and can provide a Certificate of Analysis, or COA. The lab results should show how much CBD (and THC) the product contains, as well as how the product did in tests checking for contaminants such as heavy metals and fungicides. If you can’t find a COA on the company’s website or the company refuses to share it, that's a red flag.

Though CBD seems to cause few side effects, cannabis does interact with some drugs. So, it’s important that you and your veterinarian be alert to any changes in your pet. Like many medications, cannabinoids are metabolized through the liver, so combining CBD with other drugs may enhance the effects of those pharmaceuticals. CBD often potentiates the effects of antiseizure medications, which is why a lot of times when we combine those with cannabis, we get better control.

Although some CBD products have dosing instructions on the label, little is really known about what doses are most effective and safe. For example, while initial research in dogs used 2.5 mg per kilogram twice a day, higher doses may be more effective.  Judy Morgan, D.V.M., a holistic vet in New Jersey and co-author of "Yin & Yang Nutrition for Dogs," recommends starting with 1 mg per 10 pounds of body weight twice a day—and monitoring your pet’s reaction.

Until more is known, the experts urge caution. Numbers are really useful, but cannabis is a very individualized medicine, and using tinctures rather than a chew treat can make it easier to scale dosages up or down.

In summary, I believe that CBD has a place in the treatment of pets. My research indicates that CBD has been demonstrated to be a potential aid in treating osteoarthritis and several other maladies such as epilepsy and behavior issues. If you want guidance from your veterinarian about CBD for your pet, you may have to start the conversation because veterinarians have been left out of most state laws concerning cannabis.  That being said, CBD is available in many local pharmacies, over the internet and dispensed at some veterinary facilities. Our local pharmacy does offer CBD for human and pet use. No prescription is required, and the quality of the product is good.

Dr. Lamb is the Veterinarian at the Manchester Animal Hospital.