THC/ Cannabis Intoxication

How do cats and dogs become intoxicated?

Cats and dogs can become intoxicated by cannabis in various ways, most commonly by eating edibles (e.g., baked goods, candies, chocolate bars, and chips containing cannabis), or by ingesting cannabis directly (in any form). Pets can also be exposed to second-hand smoke. Most exposures are accidental when curious pets discover access to the drug or when they are present in the same room with a person smoking cannabis. Dogs have more cannabinoid receptors in their brains, which means the effects of cannabis are more dramatic and potentially more toxic when compared to humans. A small amount of cannabis is all it takes to cause toxicity in cats and dogs.

How does cannabis affect cats and dogs?

Like most drugs, the effects of cannabis are based on chemistry. The drug enters the body via inhalation or ingestion and interacts with and alters the brain’s chemical messengers, such as norepinephrine, dopamine, serotonin, and acetylcholine.

Everything that enters the body has to exit the body. THC is very lipid-soluble, which means that it is easily stored in the fatty tissue in the liver, brain, and kidneys before being eliminated from the body. THC is metabolized in the liver and the majority (65-90%) is excreted in the feces, while a small percentage (10-35%) is eliminated through the kidneys. The drug has to be metabolized and excreted for the effects to wear off.

How toxic is cannabis?

Cannabis is considered to have a high margin of safety for people; however, not all people, and certainly not all pets, follow a single pattern of intoxication. A small amount may affect one pet more than another, so there is no official safe level of exposure. Differences in age, health status, and body size are some of the factors that can lead to toxicity differences.

Luckily, cannabis intoxication is seldom if ever fatal. However with the availability of synthetic/medical grade THC, more serious intoxication can occur.

What are the clinical signs of cannabis intoxication?

Many of the signs of intoxication are neurological. Pets may become wobbly and uncoordinated. They may be hyperactive or sleepy, disoriented, and/or very vocal. Their pupils may dilate, giving them a wild-eyed appearance, and they may drool excessively or vomit. They may also develop urinary incontinence (i.e., urine leakage). In severe cases, tremors, seizures, and coma can result.

How is intoxication diagnosed?

Diagnosis is based on an accurate history and clinical signs. Human urine drug screening tests are available and often utilized but are not as accurate in pets compared to humans.

How is intoxication treated?

When a toxin enters the body, often the first line of defense is to get it out. If the toxicity is discovered shortly after ingestion, your veterinarian may induce vomiting to prevent further absorption of the toxin. Two factors may interfere with this early defensive strategy. First, the signs of toxicity may manifest only after the drug has been absorbed, meaning it is already in the system. Second, cannabis has an anti-emetic effect that inhibits vomiting. In life-threatening cases, the stomach may be pumped (gastric lavage). Activated charcoal may be administered every six to eight hours to neutralize the toxin. Enemas are also used to reduce toxin absorption from the gastrointestinal tract.

The second line of defense in cannabis toxicity involves providing supportive care until the effects of the drug wear off- this is the treatment plan that is most often utilized. Medications and supportive care to regulate your pet's heart rate, respiration, and body temperature can be used if needed. Since your pet may be lethargic, with no desire to eat or drink, IV fluids can help prevent dehydration, support blood pressure, and maintain organ function. Gastrointestinal treatments may be needed for nausea or vomiting. To prevent self-trauma while your pet is disoriented and uncoordinated, confinement in a safe, comfortable space is helpful. Noise should be kept to a minimum to decrease sensory stimulation. Oftentimes these supportive care measures can be implemented at home, where your pet is most comfortable.

The Bottom Line

The bottom line, when it comes to cannabis use and pets, is similar to that with other drugs in the home: Be careful. Keep all forms of cannabis, medical or recreational, out of reach of your pet. Consider storage in high cabinets or in locked drawers when not in use. Keep pets in a separate and well-ventilated room, away from second-hand smoke. Remember that pets have a good sense of smell and will be tempted to eat candies, chips, chocolates, and cannabis directly if accessible.

If you notice suspicious behavior in your cat or dog and cannabis exposure is a possibility, take your pet to your veterinarian or the nearest emergency veterinary hospital for diagnosis and possible treatment.