Although secondhand smoke inhalation toxicity is possible in animals, the most common source of exposure is actually through the ingestion of baked goods containing marijuana. Dog's get into "stuff" and will eat just about anything...
Marijuana has a wide margin of safety, and ingestions are rarely fatal, but large quantities or exposure to concentrated medical-grade type may result in prolonged, extensive medical care.
Depending on the amount consumed, clinical effects in animals may begin within 30 to 60 minutes. Signs of marijuana exposure include drooling, disorientation, dribbling urine, dilated pupils, staggering, hypersensitivity to touch and sound, vomiting, tremors, hypothermia, low blood sugar and abnormal heart rate. Higher dosages may additionally cause rapid eye movements, agitation, heavy breathing, loss of balance, seizures, and even death.
Other agents, among them chocolate, pesticides, rodenticides, mushrooms, alcohol, and many medications, can produce similar clinical signs.
Confirming marijuana toxicity presents a challenge since drug screening tests can be unreliable and impractical. Some owners may be completely unaware that their pet was exposed to marijuana.
There are no specific antidotes for marijuana poisoning. Veterinary treatment is largely supportive and depends on a time and amount of ingestion. For exposures less than 2 hours, induction of vomiting followed by administration of liquid activated charcoal may aid in excretion of the toxin. Depending on the ingested dose, some pets may require multiple days of hospitalization, intravenous fluids and continuous monitoring of blood sugar level, body temperature, heart rate and rhythm.
In rare instances, patients may be unconscious for many hours. Sometimes dogs become severely agitated and have to be sedated. The majority of dogs treated for marijuana intoxication recover completely and are sent home once they are able to hold down water and food.
As medical marijuana becomes more available to the general population, there is a potential for greater exposure to it among our pets. Preventing your pet from accessing marijuana is the best way to avoid possible illness and lengthy hospitalization. In case of suspected exposure, veterinarians or pet owner may seek assistance by calling Pet Poison Helpline ($35/case) at 800-213-6680 or the ASPCA's Animal Poison Control Center ($60/case) at 888-426-4435. These services are available 24/7 and are staffed with experts in the field of veterinary toxicology.
Dr. Agata DeMarco is a veterinarian at Kingston Animal Hospital. She has a special interest in general canine and feline internal medicine, preventive pet care, and avian and exotic animal medicine.