Whatever portion does make it into the joints must undergo changes before it can be used in connective tissues. The HCl must be removed and a sulphate added. Glucosamine HCl is not stable in liquids. Published experiments have shown that more than half of the Glucosamine HCl added to a solution will break down within 27 hours. Within 4 days, these breakdown products formed completely different molecules that were 20 times larger than what was originally in the solution.
Glucosamine sulphate is the basic building block of connective tissues and fluids.
Studies have shown that 87 to 97 percent is actively taken from the gut into the blood within 30 minutes of oral administration. Nutritional support can most definitely help maintain and heal joint tissues. Be an educated consumer. Be sure that when you give your horse a supplement, you are providing nutrition, not drugs. Also be sure that you are buying the proper building blocks in the supplements you purchase.