The number of cases of marijuana intoxication in dogs has risen dramatically in recent decades. Fortunately, it’s rarely fatal, but it can bring about some worrying symptoms, and you should always seek veterinary advice if you suspect your dog has ingested this drug.
Why Has There Been Such a Drastic Rise in Reported Cases?
In 1996, California became the first state to legalize cannabis use for medicinal purposes. Marijuana is now only prohibited in a few states, and an increasing number also allow its use for recreational purposes.
As a result of the drug’s increased accessibility, there has been a significant increase in the reports of dogs suffering from marijuana toxicosis. The Animal Poison Control Center, for example, reported a staggering 765% increase in calls about pets ingesting marijuana in 2019, compared with the same period the previous year. The Pet Poison Helpline also saw an increase of more than 400% in the number of calls they took about marijuana-related incidents over a six-year period.
The increase in reported cases even prompted a retrospective clinical study that evaluated the trends of marijuana toxicosis in dogs living in a state with legalized medical marijuana usage between 2005 and 2010. There was a concerning four-fold increase in the number of cases reported to the two Colorado veterinary hospitals that were the focus of the study.
Marijuana Toxicity Exposure
There has been a much higher incidence of dogs suffering from marijuana toxicosis than cats. This is because users often mix the drug into palatable baked goods, which is a particular problem if a dog is a renowned counter surfer.
However, your dog can also suffer poisoning from eating any part of the actual plant (including the leaves, seeds, stems, and flowers), from smoke inhalation, consuming hashish oil, or even from eating the feces of an individual that has ingested cannabis.
Symptoms of Marijuana Poisoning in Dogs
- Stumbling and crossing over feet
- Dull and lethargic
- Dilated pupils
- Urinary incontinence
- Vomiting
- Tremors and shaking
- Agitation
Tetrahydrocannabinol (THC) is the potent psychoactive substance in marijuana, and dogs have a much more severe reaction to this than humans. Symptoms are typically visible within 30 minutes to an hour after ingestion of the drug, or sooner if inhaled.
Dr. Stacy Meola is a criticalist at Wheat Ridge Animal Hospital in Colorado and was also one of the lead veterinarians involved in the previously-mentioned study. She explains that “the most common sign is stumbling and crossing over their feet, and walking like they are drunk (ataxic).” In the study, 88% of the dogs presented with this symptom. Around 50% of dogs will also likely appear dull and lethargic with dilated pupils, and will flinch in reaction to fast movements toward their face.
“The most interesting sign in dogs is urinary incontinence,” says Dr. Meola, adding that around half of the dogs studied dribbled urine uncontrollably when they had marijuana in their system. “My guess is the drug would not be as popular if 50% of people dribbled urine when they used marijuana!”
Other possible symptoms include vomiting, tremors and shaking, and agitation, and some dogs can become comatose.
Treatment of Marijuana Poisoning in Dogs
Treatment is quite variable depending on the severity of the symptoms presented. Some dogs can be treated as outpatients at home, while others will require hospitalization for intravenous fluids and supportive care.
“In severely affected animals, we recommend a treatment called intralipid therapy, which is an infusion of lipid (the fat used in IV nutrition support) to help bind the marijuana and allow it to be eliminated from the body faster,” Dr. Meola says.
With proper treatment, dogs will usually recover fully within one to two days.
Why It’s Important to Seek Veterinary Support
Marijuana toxicosis is rarely deadly, and Dr. Meola is unaware of a fatality from marijuana ingestion alone. However, a high proportion of the cases of marijuana toxicosis in dogs involve combining the drug with chocolate or artificial sweeteners like Xylitol—both of which are also toxic to dogs—in the form of brownies or cookies. It’s worth noting that medical-grade marijuana butter products may present a higher risk of more serious symptoms. These butters are commonly mixed into cakes and cookies.
Regardless of how your dog’s marijuana ingestion occurs, you should always seek veterinary advice. “Because the potency of marijuana is variable and the amount in edibles is not regulated by a regulatory agency, it is very hard to know exactly how much a dog has ingested,” explains Dr. Meola. “With that said, we also do not know a toxic or fatal dose when inhaled or ingested, so it is always best to have a pet evaluated.”