Glucosamine is a compound that provides the body with the raw material needed to manufacture important components of joint cartilage. Glucosamine shows great promise in treating and possibly slowing the progression of osteoarthritis, a degenerative joint disease that is considered the most common form of arthritis. Osteoarthritis affects more than 16 million Americans, especially older people. It results from continuous wear and tear on the joints and progressive loss of both cartilage and the protective coating that covers the ends of bones in a joint.

Multiple studies have shown that glucosamine sulfate can gradually reduce pain while improving range of motion and walking speed in people with osteoarthritis. One recent study showed that glucosamine sulfate improved symptoms in people with knee osteoarthritis. Glucosamine is not as potent an anti-inflammatory agent as nonsteroidal anti-inflammatory drugs (NSAIDs) such as aspirin and ibuprofen. But numerous studies have shown that it is at least as effective as NSAIDs at decreasing pain and improving mobility, and it is much less irritating to the gastrointestinal tract.

Glucosamine is used to treat and possibly slow the progression of osteoarthritis, the most common form of arthritis.

Glucosamine is found in chitin, part of the hard outer shell of shellfish.

Glucosamine is available as a supplement in several forms, including the following:

• Glucosamine sulfate: 500, 750, and 1,000 mg capsules and tablets
• N-acetyl glucosamine: 500 and 750 mg capsules and tablets
• Glucosamine hydrochloride (HCL): 500, 750, and 1,000 mg capsules and tablets
• Glucosamine/chondroitin sulfate combination products

Pediatric

There are no known reports to date about the use of glucosamine in children. Therefore, use of this supplement in children is not recommended at this time.

Adult

Recommended therapeutic dosage is generally 1,500 mg glucosamine per day (500 mg three times a day) for one to two months. Ongoing supplementation may be required to prevent progression of osteoarthritis and reduce pain and inflammation.

The majority of studies indicate that glucosamine is safe, nontoxic, and causes only minor side effects, such as gas, bloating, and diarrhea. However, people with certain health conditions may need to take precautions. Glucosamine sulfate may contain high amounts of sodium or potassium, so individuals on a restricted diet or taking potassium-sparing diuretics should carefully check the label before taking it. People with diabetes should have their blood sugar checked regularly, since glucosamine may raise insulin resistance. Individuals with shellfish allergies should check with a health care professional before taking glucosamine.

Glucosamine may increase the anti-inflammatory activity of nonsteroidal anti-inflammatory drugs (NSAIDs) such as ibuprofen. This interaction may result in the need for lower doses of these medications. Consult your doctor to determine whether adding glucosamine supplements may be appropriate for you.

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