Cannabidiol plus krill oil supplementation improves chronic stifle osteoarthritis in dogs: A double-blind randomized controlled trial.

Osteoarthritis (OA) is the most common orthopedic disorder characterized by chronic inflammation and pain in dogs and cats. Cannabis spp. contains cannabidiol (CBD), a substance with pain relief and anti-inflammatory properties in different animals including dogs with OA. The use of CBD supplements has been increasingly intertwining in veterinary medicine. This study aimed to evaluate the clinical efficacy of CBD + krill oil-supplemented biscuit against canine OA. In total, 30 dogs with stifle OA were randomized and divided into the placebo, krill oil, and CBD + krill oil groups. The Canine Brief Pain Inventory questionnaire was used to evaluate the efficacy of each treatment against pain. Stifle temperature was monitored to identify degrees of stifle inflammation. Two and one dogs in the placebo group were excluded from the study due to worsening lameness and increased pain interference score (PIS) and pain severity score (PSS) at days 14 and 28, respectively. The PIS and PSS scores of the krill oil and CBD + krill oil groups gradually and significantly improved after two weeks of treatment. The CBD + krill oil group had better PIS and PSS scores than the placebo and krill oil groups. However, there was no statistically significant difference in the PIS and PSS scores between the krill oil and CBD + krill oil groups. The stifle temperature of the three groups at different periods did not significantly differ. In conclusion, CBD + krill oil supplements are safe against canine OA. CBD can reduce pain and inflammation.