Tread Cautiously with Betamethasone Joint Injections in Horses

Previous research by a University of Kentucky research team found detrimental effects of intra-articular injection of the corticosteroid triamcinolone when used for horses with joint disease, specifically osteoarthritis.

Intra-articular triamcinolone resulted in decreased blood cortisol levels and markedly increased glucose and insulin levels. As a result, the researchers concluded that “triamcinolone acetonide exhibits significant metabolic side effects” and indicated that this commonly used joint medication should be used cautiously. In a follow-up study, researchers evaluated the effects of intra-articular betamethasone, a similar medication as triamcinolone but one with a much shorter half-life and therefore cleared from the body faster.

Eight horses were included in the betamethasone study: five metabolically normal horses and three diagnosed with insulin dysregulation (ID). Either 9 mg betamethasone or saline were injected intra-articularly into one fetlock joint. Blood was collected at baseline before injection and intermittently up to 336 hours after injection to measure cortisol, glucose, and insulin. In addition, oral glucose testing was performed at baseline and again 48, 168, and 336 hours after injection.^*

“This small, preliminary study found that betamethasone, like triamcinolone, had far-reaching metabolic effects, such as suppressing the hypothalamic-pituitary-adrenal axis. In addition, glucose levels were also elevated,” explained Ashley Fowler, Ph.D., a nutritionist for Kentucky Equine Research.

Due to the small number of horses included, no further conclusions could be drawn, but the researchers noted that further studies are needed.

Managing joint discomfort without the use of corticosteroids can be achieved with nonsteroidal anti-inflammatory drugs, orthobiologics such as interleukin-1 receptor agonist protein (IRAP) therapy, autologous protein solution, and platelet-rich plasma, as well as oral joint health supplements.

“Sodium hyaluronate is an oral supplement that helps with maintaining the thickness of the joint fluid. Maintaining viscous synovial fluid assists in reducing inflammation and cartilage damage. Adding a supplement containing this ingredient may help maintain joint integrity in horses with joint inflammation such as osteoarthritis,” recommended Fowler.

^*Page, A.E., A.M. Rauber-Ramos, M. Humiston, J.L. McPeek, and E.N. Adam. 2025. Initial investigation into the metabolic effects of intra-articular betamethasone on normal and insulin dysregulated horses. Journal Equine Veterinary Science 147:105404.