Ultimate Glucosamine contains only 100% pure N-acetylglucosamine. It is free of additives, salts or preservatives, and contains more of the biologically active ingredient. Ultimate Glucosamine is the most direct route to the important macromolecules such as hyaluronic acid, keratan sulfate and chondroitin sulfate. Ultimate Glucosamine does not interfere with glucose metabolism. There are no known interactions with prescription medications, nor is there evidence of any specific side effects attributable to Ultimate Glucosamine. Still, you should always make your health care professional aware of all supplements you are taking.