Glucosamine is the base of chondroitin sulfate, a specific type of polysulfated glycosaminoglycan (GAG). Glucosamine increases the production of GAGs and new cartilage, but also stops the enzymes that break down cartilage. This helps keep joints lubricated and moving better.
There are 2 types of Glucosamine;
Glucosamine HCI has a harder time getting into the joint tissue because of the chemical makeup, it also has no form of sulphur so has no real effect on the body. Sometimes Chondroitin Sulfate will be added to a Glucosamine HCI to help provide that sulfur. The problem with that is Chondroitin Sulfaate has large molecules making it more difficult to get into the joints. Typically only 30% of this actually absorbed by the body, the rest ends up in the urine and feces.
Glucosamine Sulphate 2KCl (Potassium Salt) and Glucosamine Sulphate NACl (Sodium Salt) have been proved in studies to effectively get into the joint tissues. Glucosamine Sulphate is the building block of connective tissues and fluids. This supplement begins getting into the blood within 30 minutes of oral ingestion, and within 4 hours can be seen in the joint cells (Chondrocytes). A lack of sulfur in the body will stop production of connective tissues.
Too much glucosamine (of any variety) will pass through the system (sometimes causing diarrhea). Gulcosamine is an allowed substance in the USEF as it is naturally occuring in the body.
MSM (Methyl-sulfonyl-methane) is a biologically active sulfur that the body can readily use. Sulfur is necessary for the production of collagen, glucosamine, and chondroitin, all of which are building blocks of cartilage. MSM has an anti-inflammatory effect in an average horse after 10 grams and also helps form the cartilage matrix. It helps relieve any discomfort due to bone or musculature issues. It also helps reduce the amount of free radicals (damaging cells) in the joint, especially afgter a workout. MSM tends to stimulate circulation as well. SSUlfur in the body also benefits the hair, hide, hooves, connective tissue and enzymes, hormones, and immunoglobulins. Sometimes MSM has even been reported to help with allergies. MSM by itself is an allowed substance in the USEF as it is naturally occuring in the body.
When giving either of these supplements, make sure it is not combined with Yucca or other chemicals if you are going to show with an organization that does drug testing. For more information on drug testing and what is or is not allowed in the USEF, you can contact them directly.