Friday, October 19, 2018

Cannabis and Veterinary Medicine

The legislation on cannabis consumption obliges us, as veterinary practitioners, to evaluate and answer two questions.



QUESTION 1 : CAN MEDICINAL CANNABIS BE USED IN VETERINARY MEDICINE?


The possibility of medicinal cannabis in veterinary medicine has peaked interest in the veterinary profession as well as pet owners. In human medicine, cannabis has been used as an antibacterial, antioxidant, a treatment for anxiety, pain control, nausea and vomiting. It has therefore been prescribed for certain cancers, during chemotherapy, for arthritis, epilepsy and intestinal inflammatory disease.

To assume that cannabis can be prescribed for animals, for the same conditions, and to obtain the same effects, is to early to conclude. We can certainly not presume that studies done in human pharmacology will be admissive for animal medicine.

In veterinary medicine, we know that some medications that are efficient for one species do not work on others. For example, a specific molecule will not be adequate at the same dose for cat and a dog. We must also remember that certain human medications that are prescribed on a long term basis, such as acetaminophen, can severely harm your dog and cat to the extent of death.

To obtain approbation or approval of a molecule from the veterinary medicine counsel, pharmaceutical companies must provide studies of  efficiency and security at specific conditions and doses.

The medicinal use of cannabis has yet to be seriously studied on the efficiency levels in animal treatments. The fact that the substance has been illegal makes it harder to realize and execute factual studies. With the legalisation in Canada, we can now hope that the situation will change and that we will now have objective studies that will support the medicinal usage (or not) for certain conditions at a monitored dose.

UNTIL THEN, QUEBEC VETERINAIRIANS HAVE NO LEGAL OR ETHICAL WAY TO PRESCRIBE CANNABIS.

QUESTION 2 : WILL THE LEGALISATION OF CANNABIS INCREASE INTOXICATIONS IN SMALL ANIMALS?


In the United States where cannabis has been legal, statistics have shown a rise in intoxication cases.  Accidental consumption, when cannabis is in edible forms such as cookies and muffins, makes overdosing much easier. Even second hand smoke, inhaled within home boundaries will be more prevalent.  However with the legalisation, owners will be more at ease to confide the truth to their veterinarians during the exam of the animal.

The danger of intoxication can also be increased if an owner attempts to `treat` their animal with a home remedy of cannabis, especially if recreation cannabis is used, in which the THC levels are much higher.

As veterinarians, we can only warn owners against such careless actions. Although cannabis intoxication is rarely fatal, it often leads to undesirable symptoms  and puts your animal’s health at risk.

The clinical signs of intoxication are most often neurological;

Loss of balance, confusion, hypersensitivity to normal stimuli, lethargic or even hyperactivity, increased vocalisation, dilated pupils, hyper or hypothermia, loss of conscience, coma and rarely death. Sometimes vomiting can be noted, urinary incontinence, bradycardie or tachycardia (heart rate to slow or to rapid).

Clinical signs can take up to 5-30 minutes to be apparent and can last between 18 and 72 hours. In more severe cases, hospitalisation can be necessary. Depending on the age and state of the animal, complications and health risks are possible.

The legalisation of cannabis has certainly raised a fair amount of inquiries to politicians, policemen, educators and doctors. As veterinarians, we must also get informed to be able to well serve our clients and above all care for our patients.

Sources : 
Veterinary Practice news Canada, vol 1, no 1, sept 2018, 
Le Vétérinarius la revue de l’OMVQ, vol 34, no 4, automne 2018 
Blackwell’s Five minute Consult Clinical Companion: Small Animal Toxicology, second ed. 2016