Stacey Oke Compendium Equine May 2009 4 4 Oral joint health supplements are popular in the equine industry despite, in many cases, a lack of understanding of the chemistry, pharmacology (particularly safety), and appropriate dosages of these products among owners and trainers. The most popular ingredients include glucosamine, chondroitin sulfate, and methylsulfonylmethane; however, a multitude of alternative supplements, including cetyl myristoleate, hyaluronic acid, ester-C, devil’s claw, yucca, garlic, and avocado/soybean unsaponifiable extracts, are also widely available. In this article, the most up-to-date information regarding the chemistry, pharmacokinetics (primarily absorption), safety, and dosing of oral joint health supplements is relayed in a practical manner. This information can help clinicians educate clients regarding the use of supplements to ensure that horses derive as much benefit as possible.