Marijuana Toxicity in Dogs

Name of Toxin; Marijuana 

Toxicity caused by marijuana occurs when an animal inadvertently consumes a stash of marijuana. Uptake of any small amount triggers body toxicity. The poisoning is caused by a psychoactive chemical present in marijuana called tetrahydrocannabinol (THC) ( Gyles, 2016) . Ingesting marijuana plant directly, inhalation of smoke or consumption of baked products laced with marijuana triggers toxicity. 

Source of toxin and its toxic levels 

Marijuana toxin originates from cannabis sativa plant. The plant belongs to the cannabaceae family and has two common species; cannabis sativa and cannabis indica. The cannabis sativa plant is a complex species with over 400 chemical compounds such as cannabidiol and delta-9-tetrahydrocannabinol  which cause toxicity ( Strips et al., 2014) . The tops of a flowering cannabis sativa plant have high THC concentrations relative to other parts. It would only take a small amount of tetrahydrocannabinol to trigger poisoning symptoms. 

Due to the high number of cannabinoid receptors for example in a dog’s brain, a discarded joint of infused marijuana would throw the animal into distress due to resulting toxicity. Marijuana toxic levels must exceed 3g/kg when ingested orally for it to cause poisoning. The 3g/kg is the minimum dose that would be lethal. Although a dosage of 3g/kg would not cause significant harm, an amount ranging from 40 mg/kg to 130 mg/kg administered intravenously would result into death of an animal. 

Species affects 

Marijuana toxicity affects dog species. Intoxication in dogs caused by marijuana occurs in various ways. Eating edibles such as candies, ingesting directly or inhaling second hand smoke would result into toxicity. Dogs brains have a large number of cannabinoid receptors implying that effect of marijuana toxicity are more devastating and dramatic. Upon entering into a dog’s body via ingestion or inhalation, the marijuana toxin binds with brain neuroreceptors, thereby altering neurotransmitter function ( Strips et al., 2014) . THC compound affects neurotransmitters such as serotonin, norepinephrine and acetylcholine. CB1 receptor in dogs is responsible of most effects of marijuana toxicity. 

Clinical Signs 

Marijuana toxicity clinical manifestations include dilated pupils, listlessness and incoordination, urinary incontinence and a slow heart rate. Pets also display a startle reaction characterized by drowsiness and loss of balance. Additional clinical signs include whining, agitation, trouble in temperature regulation, tremors, potential coma and seizures. Dysphoria, mydriasis, hypoventilation, hyperactivity and ataxia are also clinical sign of marijuana toxicity. The signs start to manifest from 5 minutes to 12 hours after the first exposure to marijuana and usually lasts for 30 days to several days depending on ingested dosage ( Fitzgerald et al., 2013) . The dog owner should give a truthful picture about the pet’s history for accurate diagnosis. The owner should narrate the dog’s history of marijuana exposure to a veterinary. 

Diagnostic available 

Urine testing similar to that done on humans can be performed to diagnose marijuana intoxication. A large volume is required to run the urine test. The test is done to check levels of THC. Diagnosis is based on the pet’s clinical presentation. A positive urine test result would indicate marijuana poisoning. A venous blood gas test can also be used to make a diagnosis for pets suspected of hypoventillating sedative effects ( Greb & Puschner, 2018) . The test evaluates partial pressure for carbon dioxide. 

Treatment/Supportive care 

Appropriate decontamination can be used to treat marijuana poisoning. Decontamination is done through gastric lavage followed by administration of activated charcoal ( Bloom & Hofve, 2013) . Gastrointestinal support and fluid therapy are also appropriate treatment methods. Supportive care include heart rate regulation medications, IV fluids for hydration and anti-vomiting medication. 

Prognosis 

With supportive care, prognosis is excellent with supportive care since an intoxicated dog can improve and remain stable over time. Failure to seek treatment would lead to progression of symptoms and a potential fatality may ensue. 

Prevention 

Pet owners should pet-proof their residences to avoid secondary exposure to marijuana. Clients should refrain from taking marijuana substances in their homes where pets can access them. 

References 

Bloom, G. A. C., & Hofve, J. (2013). Pets and Tobacco, Vape, and Marijuana Smoke. 

Fitzgerald, K. T., Bronstein, A. C., & Newquist, K. L. (2013). Marijuana poisoning.  Topics in companion animal medicine ,  28 (1), 8-12. 

Gyles, C. (2016). Marijuana for pets?.  The Canadian Veterinary Journal ,  57 (12), 1215. 

Greb, A., & Puschner, B. (2018). Cannabinoid treats as adjunctive therapy for pets: gaps in our knowledge.  Toxicology Communications ,  2 (1), 10-14. 

Strips, O. D., Spray, M. M. C., & Calculator, D. V. S. (2014). Canine Cannabis–Marijuana for Pets.