The advantage to the intravenous product was that it completely removed the low, but real, risk of causing a joint infection or accidentally damaging the joint cartilage with a needle. In fact, it worked so well that nowadays IV injection is used more often than direct joint injections.
Effective, yes-but also expensive! Intravenous hyaluronic acid is a prescription drug, so it also requires a veterinarian fee. Moving forward to the 21st century, the first oral hyaluronic acid treatment for horses was released: hyaluronic acid in a gel form. This sounded like a great idea-but would it work? Could it even be absorbed?
At the time this product was introduced, there were no good studies to show absorption. However, orally given hyaluronic acid was being used experimentally as a carrier for insulin absorption. Proof of absorption finally emerged at the 2008 meeting of the Federation of American Societies of Experimental Biology. Radioactively labeled high-molecular-weight HA was fed to mice and dogs. By measuring radioactivity in the blood and body tissues, it was found that even this large, high-molecular-weight molecule could be absorbed (with about 13% of the dose making its way into the body).
Getting back to horses and oral hyaluronic acid: A study published in 2006 performed at the Rood and Riddle Equine Hospital in Kentucky looked at the effects of using hyaluronic acid gel postoperatively in yearlings who had surgery for osteochondrosis problems in the hock. The study included 48 yearlings, with half receiving the HA gel while the other half did not. They found significantly reduced joint swelling in the treated horses.
The dosage used for the Rood and Riddle study was 100 mg. A study presented at the 2003 meeting of the Matrix Biology Institute (a nonprofit organization devoted entirely to hyaluronic acid research) reported that the same 100 mg dose given to racing thoroughbreds reduced the number of times vets were asked to examine them for lameness.
My personal experience with hyaluronic acid is that it is extremely effective orally for getting rapid control of joints that are acutely inflamed, hot, and painful. Improvements are obvious within 24 to 72 hours. The gel and liquid forms seem to work more quickly. Hyaluronic acid is also now widely available as a powder. This form has not been studied to see how it compares for absorption or effectiveness.
Is HA For Your Horse?
If you're already using a joint supplement, should you switch to one containing hyaluronic acid? This ingredient definitely benefits horses with joints that are hot and swollen from a flare up of an old problem, an entirely new problem, or from being worked hard and regularly. If your horse has more of an old arthritis with a largely stable pattern of stiffness and no dramatic changes, it's a little more difficult to predict if HA will help. The best advice we can give you is that if your current joint supplement isn't giving you the results you had hoped for, try adding hyaluronic acid. You could try buying an HA-only product first and adding this to your current supplement, or you could switch to a combination product that contains hyaluronic acid and doses of other ingredients that are similar to your current supplement. The object here is to avoid making any changes except for the addition of the HA.
