Stanzolol for Horses with Osteoarthritis

With no cure for osteoarthritis in horses, the main management strategy remains slowing disease progression. For many, this involves a multimodal approach, including anti-inflammatory drugs administered either systemically or directly into the joint and oral joint health supplements with anti-inflammatory properties. While many veterinarians first reach for methylprednisolone or triamcinolone when medicating arthritic joints, new research shows* that stanzolol may be useful as an intra-articular medication for osteoarthritis.

“Any trauma or insult to a joint sets off a chain of events that eventually results in degradation of the articular cartilage. Slowing down this painful degeneration of the cartilage remains the focus of treatment efforts, with secondary efforts aimed at restoring a functional joint environment that could potentially promote cartilage repair,” explained Laura Petroski, B.V.M.S., a veterinarian for Kentucky Equine Research.

Unlike the four FDA-approved corticosteroids available for intra-articular administration in horses, stanzolol is an anabolic-androgenic steroid synthetically derived from testosterone. While some anabolic-androgenic medications promote male characteristics due to their similarity to testosterone, stanzolol has high tissue-building activity with minimal androgenic side effects.

To determine whether stanzolol could improve the tissue-building activity in articular cartilage, a group of researchers from the United Kingdom cultured cartilage cells and measured the effect of stanzolol on cell viability, inflammation, and genes involved in the growth and breakdown of cartilage.

“The study revealed that stanzolol exerted chondroprotective effects by decreasing the genes for pro-inflammatory mediators and catabolic molecules and enzymes associated with osteoarthritis. Unfortunately, this study did not show any evidence of cartilage growth as anticipated,” Petroski shared.

Considering the merits of stanzolol in a myriad of human conditions, including rheumatoid arthritis and diseases involving muscle-wasting, research with this medication for osteoarthritis continues. Horse owners, therefore, must continue to rely on evidence-based strategies for managing osteoarthritis, which include the following:

• Ensuring horses maintain an appropriate body condition score to limit excess stress on joints;
• Avoiding injuries due to inappropriate work (e.g., increasing work too quickly, competing an unfit horse);
• Administering anti-inflammatory drugs to control inflammation, including intra-articular corticosteroids or systemic nonsteroidal anti-inflammatory drugs;
• Using extracorporeal shockwave therapy; and
• Offering high-quality nutritional supplements with ingredients demonstrated to support joint health.

“Products containing glucosamine and chondroitin sulfate benefit horses with osteoarthritis by protecting joints when used prophylactically before an injury or insult has occurred,” said Petroski.

Kentucky Equine Research offers several quality joint supplements, including KER•Flex with glucosamine and chondroitin sulfate, Synovate HA with high molecular weight hyaluronic acid, and EO•3 containing marine-derived fish oils.

Australian horse owners should also look for Glucos-A-Flex.

*Castro Martins, M., M.J. Peffers, K. Lee, et al. 2018. Effects of stanozolol on normal and IL-1β-stimulated equine chondrocytes in vitro. BMC Veterinary Research 14(1):103.