In a study published earlier this year, the University of Guelph investigated the effects of cannabis legislation on cannabis poisoning cases in dogs. The report found that in states with lower penalties for cannabis use, there was an increase in reports of dog poisoning events. Reporting of cannabis poisonings were more likely to come from vets, rather than dog owners. Often in dog poisoning cases involving narcotics, there is a delay to treatment of the affected animal for fear of being penalised. The research team hope that increased awareness to the public, and the veterinary communities, of the effects of drug exposure on dog populations will help prevent exposure, as well as reducing the length of time until treatment.

In the cases reported to the VPIS, dogs are commonly exposed following ingestion, or accidental inhalation of smoke. The onset of clinical signs is rapid if inhaled (usually within 6-12 minutes), or ingested (30-90 mins). Dogs who ingest a small dose of plant material may recover within 24 hours, but those ingesting larger doses may show clinical signs for several days. CNS depression, ataxia (often pronounced in the hind limbs), and bradycardia are the most common signs in animals exposed to cannabis. Behavioural changes include aggression, agitation, barking and hallucinations. Treatment is recommended for any amount of cannabis, and is largely supportive.

Veterinary practices can call the Veterinary Poisons Information Service on 02073055055 for treatment advice.