Dietary Supplement. Joint health. Shown to help build and support joint cartilage. Enzymatic Therapy. What better feels like. Clinical studies show glucosamine sulfate is a key building block for connective tissue and cartilage. The glucosamine sulfate in doctor-recommended GS-500 dietary supplement is up to 90% absorbable, which makes it more readily available to the body to support healthy articular cartilage. GS-500 is the original glucosamine sulfate product in the United States - the standard by which all the rest are judged. ETI is an FDA-registered Drug Establishment. Laboratory tested - Purity, safety & performance. enzy.com. Contains no sugar, yeast, wheat, gluten, corn, soy, dairy products, artificial coloring, artificial flavoring, or preservatives. This product contains natural ingredients; color variations are normal. (This statement has not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.)