Osteoarthritis of the Knee

Popular supplements don’t work

Many people with osteoarthritis have knee pain. They often try over-the-counter treatments to help the pain, and to avoid knee surgery. The supplements, glucosamine and chondroitin sulfate, are very popular. In 2012, Americans spent $813 million on these supplements, according to the Nutrition Business Journal.

The knee pain is caused by the breakdown of the cartilage. This is the tough flexible tissue that covers the ends of the knee and other joints. Glucosamine and chondroitin are building blocks of cartilage. But they are not good for pain relief. Here’s why:

These popular supplements don’t work.

Many studies have shown that glucosamine and chondroitin sulfate do not help to relieve arthritic knees. People who take the supplements often report less pain or swelling of their joints. But people get similar results if they take a placebo—a “sugar pill” with no active ingredients. Pain relieving drugs, such as acetaminophen and ibuprofen, help a lot more.

The supplements can be dangerous.

Glucosamine and chondroitin are not harmful by themselves, but they can interact with other medicines. For example, the supplements can increase the effect of warfarin (Coumadin and generics) on blood clotting. This increases the risk of bruising and serious bleeding. Problems with warfarin cause a third of all emergency room visits among seniors in the U.S.

These supplements are a waste of money.

You will spend about $130 a year if you take a glucosamine/chondroitin supplement every day.

To make matters worse, often the labels on the bottles are misleading. In 2013, Consumer Reports tested 16 joint pain supplements and found that seven had less chondroitin than the label listed.

Other approaches often work better.

There are more effective ways to relieve arthritic knee pain:

  • Physical therapy
  • Losing weight
  • Acetaminophen (Tylenol and generic)
  • Ibuprofen (Advil and generic)
  • Naproxen (Aleve and generic)

If these don’t help, you can talk to your doctor about treatments such as injections or surgery.

This report is for you to use when talking with your health-care provider. It is not a substitute for medical advice and treatment. Use of this report is at your own risk.

© 2014 Consumer Reports. Developed in cooperation with the American Academy of Orthopaedic Surgeons.