
Itchy and Scratchy
When people have allergies, we typically sneeze and develop watery eyes and runny noses. But dogs (and cats to a lesser extent), are more likely to scratch, lick, and rub at their skin, especially their feet, flanks, ears, rump, and armpits. Dogs can develop “hot spots” from licking and biting at an itchy area, creating a weepy inflamed and painful area overnight on their skin. Compared to us, dogs and cats have more histamine-releasing mast cells in their skin. Histamine causes inflammation and allergic reactions, especially in response to flea saliva, pollen, dust, mold, grass and foods. Some are even allergic to naturally occurring bacteria on the skin.
Allergic dermatitis (AD) is one of the most common and frustrating problems veterinarians wrestle with because it lacks a clear solution. Bathing to remove allergens and soothe the skin can provide modest improvement. Antihistamines can help, but they can cause drowsiness. Omega-3 and Omega-6 fatty acids supplements help in about 20% of cases. Corticosteroids reduce itching but at the cost of undesirable side effects with long-term use. Immunotherapy, like the allergy shots for people, are slow to work, if they work at all.
CBD and Pet Allergies
Anecdotally, CBD has been shown to be helpful for some dogs. In a Colorado State University College of Veterinary Science survey of dog owners who used CBD, 62% reported that CBD helped their dogs’ skin conditions, and 92% reported it reduced inflammation.
And theoretically, CBD should help. Dog skin contains CBD1 and CBD2 receptors, both of which reduce inflammation and pain perception. Cannabis reduces antibodies that trigger histamines, so CBD should be helpful in reducing antibody response to allergens.
Experimentally, lab mice bred to have deficient cannabinoid receptors display greater allergy signs and CBD reduces itching in mice and rats. The cannabinoid palmitoylethanolamide (PEA) reduces or delays itching in dogs and cats (PEA can be found in foods such as egg yolks, beans and dairy products, but the latter may not be tolerated by many dogs and cats). CBD ointment also reduces inflammation and itchiness in people with AD.
CBD Pet Allergy Research
As of yet, no results from experimentally controlled studies are available concerning CBD and allergic dermatitis in dogs, but that is changing. Melissa Loewinger, DVM of Animal Dermatology and Allergy Specialists in Riverdale, NJ and White Plains, NY, is looking for a few good—itchy—dogs to complete her study. Your dog could contribute to science and get some perks in the process if he’s local to the clinic and accepted into the study. To find out more, please visit animaldermatologyspecialists.com. Loewinger has already started collecting data but it’s too early to comment on results.
From a practical viewpoint, CBD falls in the “really worth a try” category. Since the terpene alpha-pinene has also been shown to decrease mouse allergic reactions, try CBD products with alpha-pinene and/or PEA if possible or try a broad spectrum product from SperoCBD. And be sure to include Omega-3 and -6 fatty acids in your pets diet.
Ingested CBD products are best for generalized itchiness. While topicals may be preferred for localized problems in people they’re not always the answer for pets. Many products, especially those designed for human use, contain ingredients that can be toxic for pets if licked or ingested. If the directions say “Do not ingest” then they are not safe for pets.
References
Colorado State Survey: https://canna-pet.com/canna-pet-customer-survey-results/
Cannabis reduces antibodies that trigger histamines: https://jlb.onlinelibrary.wiley.com/doi/pdf/10.1189/jlb.0608390
Lab mice bred to have deficient cannabinoid receptors display greater allergy symptoms: https://pubmed.ncbi.nlm.nih.gov/17556587/
2019 study found CBD ointment rubbed into people’s skin reduced inflammation due to atopic dermatitis: http://www.clinicaterapeutica.it/ojs/index.php/ClinicaTerapeutica/article/view/377/147
Alpha-pinene: https://www.sciencedirect.com/science/article/pii/S1567576914003622
Dog and cat studies cited in this article:
Cannabinoid receptor type 1 and 2 expression in the skin of healthy dogs and dogs with atopic dermatitis file:///C:/Users/CC/AppData/Local/Packages/Microsoft.MicrosoftEdge_8wekyb3d8bbwe/TempState/Downloads/Cannabinoid_receptor_type_1_and_2_expression_in_the_skin_of_healthy_dogs_and_dogs_with_atopic_dermatitis%20(1).pdf
Study call for subjects: https://www.animaldermatologyspecialists.com/current-events/2019/7/28/calling-all-itchy-dogs