In part I and part II we discussed the history of CBD, how it works, and the legality behind CBD for pets & people. While this can all seem a little overwhelming, especially considering the wide availability of CBD – the main take away is that it is important to be safe when choosing any supplement. One of the reasons I decided to put together such a robust series was to explain why it was so important to look for quality and transparency in products. I can tell you all day that quality and transparency are important, but if I don’t explain the reasoning, it just becomes a hollow message.
Part III dives into the clinical data available for CBD use in pets. We’ll also look at what to do if your pet ingests marijuana. Unfortunately, this is a common incident, and THC within marijuana products is an emergency. Finally, we’ll discuss why there is not more available data on dosing, and just why this may be different for each pet.
Hemp & Marijuana: Available Data, Risks & Clinical Information
No established long-term safety data for Hemp/CBD in pets, however, this is not unlike many pharmaceutical medications and supplements already on the market.15 Recent short term data from a recent small study of cats and dogs given 2mg of CBD twice daily for 12 weeks determined that CBD was not detrimental to complete blood counts (CBC) or biochemistry values. It was determined that CBD in cats is metabolized differently than dogs, and needs further evaluation to determine appropriate dosing.4 Additionally, one cat experienced rising levels of ALT, a liver enzyme, which also requires further investigation.16 Additional studies have shown an elevation in ALP, another liver enzyme, further identifying the need for more research.17 This is in line with findings on the human side regarding use of CBD.18
Marijuana itself does have well-documented risks for pets that stem from THC. Even though this is not used or recommended for pets, exposure is common through the ingestion of their owner’s marijuana supply. The minimum lethal oral dose for dogs for THC is more than 3 g/kg, and has been seen most commonly with the ingestion of THC butter.4 Treatment of THC/marijuana ingestion in animals is largely supportive. Meaning that no specific antidote presently exists for THC poisoning. The majority of dogs experiencing intoxication after marijuana ingestion recover completely without long term effects or deficit.4
Clinical effects of toxic levels of THC/marijuana ingestion are generally seen within 60 minutes. Signs of canine intoxication include depression, hypersalivation, mydriasis, hypermetria, vomiting, urinary incontinence, tremors, hypothermia, and bradycardia. Higher dosages may additionally cause nystagmus, agitation, tachypnea, tachycardia, ataxia, hyperexcitability, and seizures.4 If you suspect your pet has ingested marijuana seek immediate veterinary care.
Toxin Concerns: Phytoremediation
In our last article, we discussed the lack of accountability and product adequacy testing within the human and pet supplement market. When it comes to toxic screening, cannabis in all form are of concern, because it can be a highly toxic plant. This is because it performs a process called phytoremediation and therefore adds another level of concern to the equation. Phytoremediation means that cannabis absorbs heavy metals and many of the agricultural chemicals in the soil such as pesticides, herbicides, and fertilizers. Many CBD companies like to hide behind the word ‘proprietary’ when it comes to analysis or ingredient sourcing. However, this is not an excuse that holds any weight when it comes to the safety of cannabis, period. Fortunately, the National Animal Supplement Council (NASC) works with some CBD companies to help protect against contaminated CBD products and other supplements from entry to the marketplace. In other words, it is wise to avoid pet supplements without the NASC seal. We discussed the NASC in more detail in Article II.
Dosing for CBD Products
A variety of CBD containing products are on the market for people and pets. These include oral oils, pills, capsules & food products like treats and honey. There are also balms and other transdermal-type products that are designed for use on skin. Products have varying levels of effectiveness that likely have to do with quality, purity, concentration, and dosage. Exact dosing of CBD dosing for pets is still being established and is largely up for debate. Further complicating this issue is that some hypothesize this could be highly individualized.
Fortunately, CBD containing hemp products, by law, are to have 0.3% THC or less on a dry weight basis, so the risk of overdose from THC is quite low.9 This does not however mean that dosing CBD, hemp products in pets should not be measured or monitored. Always follow veterinarian and/or product label instructions.
We’ve all heard the claims of benefits for CBD for both pets and people, however, we now know that those claims are largely unsupported by science and that companies are likely in violation when making these claims. Regarding safety, it appears that there are few adverse events. For CBD have been reported, however, some studies point to a potential for concerns for liver values. This area needs further research, and we’re sure that more data will be available in the near future. If your pet has had or currently has any liver concerns, it is important to discuss CBD use with your veterinarian prior to using it. In addition, if you decide to use CBD it is paramount to ensure the product is NASC compliant. There are also several questions that you can ask your CBD (or any supplement company) which we will discuss in Part IV! Did you miss part I and part II of the CBD & Hemp series?
- Sawler J, Stout JM, Gardner KM, et al. The Genetic Structure of Marijuana and Hemp. PLoS ONE. 2015;10(8). doi:10.1371/journal.pone.0133292
- Marijuana, the Second Trip. Revised Edition by Bloomquist, Edward R.: Good PAPERBACK | Earthlight Books. Accessed June 3, 2020. https://www.abebooks.com/Marijuana-Second-Trip-Revised-Edition-Bloomquist/22676164305/bd
- Kogan L, Schoenfeld-Tacher R, Hellyer P, Rishniw M. US Veterinarians’ Knowledge, Experience, and Perception Regarding the Use of Cannabidiol for Canine Medical Conditions. Front Vet Sci. 2019;5. doi:10.3389/fvets.2018.00338
- Fitzgerald KT, Bronstein AC, Newquist KL. Marijuana Poisoning. Top Companion Anim Med. 2013;28(1):8-12. doi:10.1053/j.tcam.2013.03.004
- Mackie K. Cannabinoid Receptors: Where They are and What They do. J Neuroendocrinol. 2008;20(s1):10-14. doi:10.1111/j.1365-2826.2008.01671.x
- Maroon J, Bost J. Review of the neurological benefits of phytocannabinoids. Surg Neurol Int. 2018;9. doi:10.4103/sni.sni_45_18
- Levinsohn EA, Hill KP. Clinical uses of cannabis and cannabinoids in the United States. J Neurol Sci. 2020;411:116717. doi:10.1016/j.jns.2020.116717
- Mechanisms of CB1 receptor signaling: endocannabinoid modulation of synaptic strength | International Journal of Obesity. Accessed June 5, 2020. https://www.nature.com/articles/0803273
- Commissioner O of the. FDA Regulation of Cannabis and Cannabis-Derived Products, Including Cannabidiol (CBD). FDA. Published online March 10, 2020. Accessed June 4, 2020. https://www.fda.gov/news-events/public-health-focus/fda-regulation-cannabis-and-cannabis-derived-products-including-cannabidiol-cbd
- Commissioner O of the. FDA Warns Companies Illegally Selling CBD Products to Treat Medical Conditions, Opioid Addiction. FDA. Published April 26, 2020. Accessed June 6, 2020. https://www.fda.gov/news-events/press-announcements/fda-warns-companies-illegally-selling-cbd-products-treat-medical-conditions-opioid-addiction
- How CBD pet product brands avoid federal warnings. Accessed June 12, 2020. https://www.petfoodindustry.com/articles/8793-how-cbd-pet-product-brands-avoid-federal-warnings
- Drug Scheduling. Accessed June 6, 2020. https://www.dea.gov/drug-scheduling
- AVMA weighs in at cannabis hearing. American Veterinary Medical Association. Accessed June 17, 2020. https://www.avma.org/javma-news/2019-08-15/avma-weighs-cannabis-hearing
- FAQs. NASC LIVE. Accessed June 13, 2020. https://nasc.cc/faqs/
- Resnik DB. Beyond post-marketing research and MedWatch: Long-term studies of drug risks. Drug Des Devel Ther. 2007;1:1-5.
- Deabold KA, Schwark WS, Wolf L, Wakshlag JJ. Single-Dose Pharmacokinetics and Preliminary Safety Assessment with Use of CBD-Rich Hemp Nutraceutical in Healthy Dogs and Cats. Animals. 2019;9(10):832. doi:10.3390/ani9100832
- McGrath S, Bartner LR, Rao S, Kogan LR, Hellyer PW. A Report of Adverse Effects Associated With the Administration of Cannabidiol in Healthy Dogs. :5.
- Commissioner O of the. What You Need to Know (And What We’re Working to Find Out) About Products Containing Cannabis or Cannabis-derived Compounds, Including CBD. FDA. Published online March 3, 2020. Accessed June 12, 2020. https://www.fda.gov/consumers/consumer-updates/what-you-need-know-and-what-were-working-find-out-about-products-containing-cannabis-or-cannabis
- Wakshlag JJ, Cital S, Eaton SJ, Prussin R, Hudalla C. Cannabinoid, Terpene, and Heavy Metal Analysis of 29 Over-the-Counter Commercial Veterinary Hemp Supplements. Vet Med Res Rep. 2020;11:45-55. doi:10.2147/VMRR.S248712