The issue of \u201cpot and pets\u201d is a complicated one for veterinarians. More than half of U.S. states have passed legislation permitting medicinal use of marijuana in humans, but these laws apply to people only; they do not apply to animal patients. Veterinarians lack the legal authorization for veterinary use and are not protected in recommending its use. Pet owners who are using medical marijuana for a variety of ailments for themselves or who are aware of cannabis-derived products, are now asking veterinarians about using these products for their pets. Although cannabinoids such as CBD appear to be therapeutically beneficial for conditions such as for the treatment of epilepsy and the management of pain and inflammation associated with osteoarthritis, the available scientific evidence pertaining to their use in animals is limited. Further complicating the issue is that with recreational marijuana becoming law in a number of U.S. states, accidental exposures in pets are on the rise.<\/p>\n
When Illinois Governor JB Pritzker signed HB 1438<\/a> into law in June, making Illinois the 11th state to legalize recreational marijuana, the American Veterinary Medical Association (AVMA) issued a statement<\/a> encouraging all pet owners to make sure an increase in legalization doesn\u2019t lead to an increase in pet poisonings.<\/p>\n While marijuana use can be a pleasurable experience for people, the AVMA said<\/a>, it can be dangerous for dogs. Tetrahydrocannabinol (THC), the psychoactive substance in marijuana that produces a high for humans, is toxic to dogs, and can cause vomiting, incoordination, depression, sleepiness or excitation, low blood pressure, low body temperature and seizures. Death is rare, says the AVMA, but there have been a few cases reported.<\/p>\n In 2019, the ASPCA\u2019s Animal Poison Control Center reported<\/a> a 765% increase in calls about marijuana ingestion by animals over the same period last year. The Pet Poison Helpline has reported<\/a> an over 400% increase in marijuana-related calls over the past six years.<\/p>\n \u201cThere\u2019s a lot of factors to it,\u201d says Samuel D. Stewart, DVM, DACVECC, at Boston West Veterinary Emergency and Specialty<\/a>. \u201cWe legalized recreational use in Massachusetts, and since the recreational dispensaries opened, we\u2019ve seen an increased number of pets brought in for ingestion of cannabis products. People who never had cannabis products in their house don\u2019t think, \u2018Maybe I should put this up and away from where my pet can\u2019t get to it.\u2019\u201d<\/p>\n Edible products \u2014 such as pot brownies, candy bars and other baked goods \u2014 are especially concerning. Due to its \u201cfat-loving\u201d (lipophilic) nature, THC is highly concentrated in the butter used for such edible products compared to plant material, says the AVMA. Consequently,\u00a0 these products can cause pets to become particularly ill. These products could pose an increased risk due to additional toxic ingredients, such as chocolate, raisins or sugar-free sweeteners such as xylitol, which could compound their toxicity.<\/p>\n A 2012 study<\/a> published in the Journal of Veterinary Emergency and Critical Care<\/em> showed that cases of marijuana toxicosis at two Colorado veterinary hospitals quadrupled over a five-year period (2005-2010). During this period, the number of state medical marijuana registrations increased by more than 100 percent. Two dogs died after eating baked goods containing tetrahydrocannabinol (THC), the active ingredient in cannabis, the study reported.<\/p>\n Exposure to marijuana is rarely fatal in dogs, according to a study<\/a> published in Topics in Companion Animal Medicine<\/em>. The minimum lethal oral dose for THC is more than 3 g\/kg, which is more than 1,000 times the dosage where the pet owner can begin to notice behavioral symptoms, such as a glazed look. While the drug has a high margin of safety, medical-grade THC butter is more concentrated, and this is what may have caused the deaths of the two dogs in the Colorado study.<\/p>\n Marijuana is the dried material of the plant Cannabis sativa<\/em>. Herbal preparations contain over 400 compounds, including 60 cannabinoids, according to a 2012 article<\/a> published in Therapeutic Advances in Psychopharmacology<\/em>. The most potent psychoactive cannabinoid is THC (delta 9 tetrahydrocannabinol).<\/p>\n Dogs tend to be indiscriminate eaters, but even if Fido were to wolf down the flowers of a marijuana plant, there wouldn\u2019t be any adverse effect, says Dr. Stewart. \u201cThat\u2019s because the flowers have to be heated first to convert to its active form \u2014 if a dog were to eat just a bag of flower, nothing\u2019s going to happen,\u201d he says. \u201cThey have to eat either an edible or perhaps the oil used for people who are vaping.\u201d Dr. Stewart says most cases at Boston West are due to the pet ingesting edible products.<\/p>\n Fortunately, most marijuana exposures are not serious. \u201cIt\u2019s not really a marijuana intoxication \u2014 the dog is going to be just fine,\u201d says Dr. Stewart. \u201cI prefer the term ingestion. They\u2019re not poisoned from this. They dog will eat a whole bunch of edibles, for example, and they have symptoms. How much does the pet have to ingest for it to be lethal? That number is astronomically high.\u201d<\/p>\n Before recreational pot was legalized in Massachusetts, only 25% of clients would be honest about what their pets had ingested when coming to the clinic, says Dr. Stewart. \u201cEven before it was legal, we as doctors don\u2019t care if you have cannabis in the house. We don\u2019t care if you smoke it. Most people think we\u2019re going to report them. That\u2019s rarely ever the case. But there\u2019s that stigma that people don\u2019t want to tell you. Even though now it\u2019s legal, that stigma is still there, but about 50% of people bringing their pets in now [since the state legalized recreational use] are honest [that the ingestion took place in the home].\u201d<\/p>\n The ASPCA\u2019s Animal Poison Control Center (APCC<\/a>) Medical Director Dr. Tina Wismer says that \u201cthe abundance of edibles makes marijuana more enticing to dogs, since they often smell and taste like regular baked goods. Cats, on the other hand, are more attracted by marijuana in its bud form.\u201d<\/p>\n The typical presentation in the clinic is a dog that has a dazed expression, glassy eyes, incoordination, slow response times, and dribbling urine. \u201cThey\u2019re really high, but they\u2019re not going to die,\u201d says Dr. Stewart.<\/p>\n An animal that has been exposed to marijuana generally has signs and symptoms that include depression, ataxia, mydriasis, bradycardia, hypothermia and urinary incontinence, says the APCC. While there are many toxins that can cause ataxia and lethargy, urinary incontinence is not as common and can be a clue as to the exposure. Pets exposed to marijuana may exhibit other signs such as agitation and tachycardia; seizures and coma, although not common, may occur as well.<\/p>\n \u201cThe symptoms of cannabis ingestion are incredibly obvious,\u201d says Dr. Stewart. \u201cMy technicians diagnose it before I even see the dog. The flip side is that if it\u2019s not cannabis ingestion, then it\u2019s nothing good; it\u2019s something really serious. So I tell clients, \u2018If it\u2019s cannabis ingestion, I just need you to tell me, because if it\u2019s not, it\u2019s going to be something way worse.\u2019 That\u2019s the challenging part [of pet owners not being honest].\u201d<\/p>\n Fortunately, most marijuana exposures are not serious.<\/p>\n Dr. Stewart is interested in \u201cboth sides of the coin.\u201d In addition to being a specialist in emergency and critical care at Boston West, he is also involved in Ethos Discovery<\/a>\u2019s upcoming clinical study on cannabidiol<\/a> (CBD) for the treatment of pain in dogs with osteoarthritis. Once underway, the study will evaluate the pharmacology profile of CBD in dogs (i.e., how it\u2019s processed in the body), as well as its effectiveness in treating pain in dogs with chronic osteoarthritis.<\/p>\n \u201cThere\u2019s a humongous potential for actual therapeutic benefit of CBD products,\u201d says Dr. Stewart. \u201cI support people who want to use these products, but there\u2019s no good avenue for them to do it now. What I tell people is that I believe in the science behind it, but there\u2019s not been the research done [to inform our recommendations]. We don\u2019t know what the dose should be, what the frequency should be, what actual applications for what diseases we can use it for.\u201d<\/p>\n In July 2019, the AVMA submitted comments<\/a> to the FDA urging the agency to provide regulatory clarity about the labeling, safety, and use of cannabis-derived and cannabis-related products.<\/p>\n The ethical challenge for veterinarians regarding cannabis is the debate over medical use for pets. Pet owners using marijuana for medical purposes may approach veterinarians about the possibility of treating similar conditions \u2014 such as pain, seizures, and cancers \u2014 in their pets. These clients want to know whether these products are legal, safe, and effective for treating their pets\u2019 medical conditions.<\/p>\n In a recent Facebook poll that we conducted on Today\u2019s Veterinary Practice\u2019s Facebook page, 73% of 180 respondents said clients have asked them about cannabinoid treatments for their pets:<\/p>\n One issue is that these CBD products are not produced by FDA-regulated companies. \u201cThere\u2019s no regulation guiding how they make their products,\u201d says Dr. Stewart. \u201cThere\u2019s not a wealth of research being done. There\u2019s a few studies; the majority of work that\u2019s been done is at Colorado State, and Cornell. You can probably count on one hand the number of studies that are being done.\u201d<\/p>\n The AVMA encourages well-controlled clinical research and getting FDA approval by manufacturers of cannabis-derived products so that high-quality products of known safety and efficacy can be made available for veterinarians and their patients.<\/p>\n Clinical researchers face obstacles, however. On the federal level, marijuana is classified as a Schedule I narcotic \u2014 with the exception of hemp, a type of cannabis that was recently descheduled through passage of the 2018 Farm Bill \u2014 and is difficult to obtain legally for purposes of scientific research. Rescheduling marijuana could allow veterinary researchers easier access for medical studies.<\/p>\n \u201cThat\u2019s my big hope. I\u2019m happy to see so many companies making products and putting them on the market, but they\u2019re putting them on the market and they\u2019re advertising it as treating a specific condition. I\u2019m hoping the research will advance quickly. CBD is a good launching point. I hope the studies will show that there\u2019s a reason to be looking at whole plant cannabis.\u201d<\/p>\n Read a recent survey<\/a> of what veterinarians know about medical marijuana.<\/p>\n Read about Colorado State\u2019s study about cannabis and dogs with epilepsy<\/a>.<\/p>\n Visit the Toxicology Archives<\/a> of Today\u2019s Veterinary Practice.<\/p>\nPets and Marijuana Exposure<\/h3>\n
Getting an Accurate History<\/h3>\n
Clinical Signs of Marijuana Ingestion<\/h3>\n
Veterinary Medicine and Cannabis<\/h3>\n
Ethical Considerations<\/h3>\n
Learn More<\/h3>\n