Cannabis sativa (marijuana) is a common recreational drug worldwide and accidental ingestion or inhalation by dogs has been reported.
Cannabis is poorly absorbed from the canine gut and inhalation appears to induce many of the clinical symptoms. This drug, which has both anticonvulsant and antiepileptic properties, produce a biphasic parasympathomimetic/sympathetic response, inducing bradycardia, hyperglycemia, pulmonary hypertension and reduced intraocular pressure.
Toxicity signs develop after a minimum dose ingestion of 84.7 mg/kg of the active ingredient cannabidiol, with toxicity developing within 5 minutes and may persist for 3 - 4 days, depending on dog's age and duration of exposure.
Treatment usually consists of supportive therapy including intravenous fluids, diazepam and thermoregulation.
Most dogs recover from acute toxicity, although intermittent temporary psychotrophic effects have been reported up to 6 months post-exposure.
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