Lots of my patients use glucosamine and chondroitin, and would like to know more about these supplements. Here is some useful information from the Arthritis Research Campaign:

Osteoarthritis is the commonest form of arthritis. It particularly affects the weight-bearing joints of the legs and back, becoming more common with age. Many people take glucosamine sulphate tablets with or without added chondroitin. Cartilage contains substances related to glucosamine and chondroitin and taking supplements of these natural ingredients may nourish damaged cartilage.

The research findings are conflicting, but more evidence is accumulating that some people, at least, will benefit from this therapy. Much of the research has been undertaken on people taking a combined daily dose of 1500 mg of glucosamine and 1200 mg of chondroitin and so this would be a good combination dose to use if you wish to try them. They can also be taken separately if you prefer. Glucosamine should not be taken by people who have an allergy to shellfish, although there is now a vegetarian version that can be substituted. In some people glucosamine can increase the level of sugar in the blood, so if you have diabetes be sure to check your blood sugar and discuss with your doctor if your blood sugars seem to be higher. Also if you are taking warfarin your blood-thinning control (international normalised ratio, or INR) may be affected, so make sure you have your regular blood checks and again discuss this with your doctor. Try glucosamine and chondroitin supplements for 3 months and if your joint pain is much improved you may wish to continue with them.