For many years, glucosamine and chondroitin – both separately and combined – have been some of the most commonly used supplements for osteoarthritis (OA). While evidence in the past has been conflicting as to whether they’re effective, research now concludes that they’re not effective for treating OA of the hip or knee.
And in the case of glucosamine, it may have harmful side effects for people with a shellfish allergy or taking certain medicines.
At the ends of most of our bones, we have a slippery cushion called cartilage. It absorbs shocks and helps our joints move smoothly. For people with osteoarthritis, this cushiony cartilage becomes brittle and breaks down. Some pieces of cartilage may even break away and float around inside the joint, causing inflammation and pain. The cartilage no longer has a smooth, even surface, so the joint becomes stiff and painful to move.
Glucosamine is a naturally occurring sugar found in our cartilage. One of the roles of glucosamine is to build and repair cartilage.
Glucosamine supplements come in two forms – glucosamine sulfate and glucosamine hydrochloride. They’re typically made from crab, lobster or shrimp shells; however, synthetic forms are also available. Supplements come in tablet or liquid form and are often combined with chondroitin.
Chondroitin is another natural substance found in cartilage. One of its jobs is to help draw water and nutrients into the cartilage, keeping it spongy and healthy (1). Chondroitin supplements are available as chondroitin sulfate. They’re made from cow or shark cartilage and are available in tablet, capsule or powder form.
Osteoarthritis is a painful condition, but we don’t currently have a magic pill that can treat it quickly and effectively. Pain-relieving medicines (analgesics) such as paracetamol and anti-inflammatories may temporarily relieve pain and inflammation. But they’re not a cure or long-term treatment.
This explains why, to some extent, glucosamine and chondroitin became so popular when they became available. Many research studies highlighted the benefits of this new, ‘natural’ treatment. The studies seemed to provide evidence that these supplements provided pain relief for many people with osteoarthritis and improved their joint function.
However, as more research has taken place, the evidence for using these supplements has come under more and more scrutiny. The earlier studies that had been the basis for the positive recommendations for using glucosamine and chondroitin were often small and of low quality.
Because of this lack of good quality evidence, peak bodies such as the American College of Rheumatology (2) the Australian Rheumatology Association (3) and the Royal Australian College of General Practitioners (4) recommend against the use of glucosamine and/or chondroitin to treat osteoarthritis of the hip and/or knee.
Glucosamine supplements are usually made of shellfish, so if you have a shellfish allergy, you shouldn’t use them. Glucosamine can also affect your blood sugar levels and may adversely affect diabetes, cholesterol, chemotherapy and blood-thinning medicines. Before taking glucosamine, talk with your doctor or pharmacist for information.
The good news is that there are other very effective treatments for osteoarthritis, including.
If you’ve been taking these supplements for some time, you haven’t had any adverse side effects, and you want to continue taking it, talk with your doctor or pharmacist for information and support.
Call our MSK Help Line and speak to our nurses. Phone 1800 263 265 or email firstname.lastname@example.org. We can help you find out more about:
(1) The Royal Australian College of General Practitioners Guideline for the management of knee and hip osteoarthritis
(2) American College of Rheumatology/Arthritis Foundation Guideline for the Management of Osteoarthritis of the Hand, Hip, and Knee
(3) Australian Rheumatology Association and Arthritis Australia Statement regarding the use of glucosamine for the treatment of Osteoarthritis
(4) The Royal Australian College of General Practitioners Guideline for the management of knee and hip osteoarthritis