Glucosamine and chondroitin

This sheet has been written to provide general information about glucosamine and chondroitin for people with arthritis. This sheet includes information about the effectiveness of these supplements and the possible risks.

Introduction

Research is mixed on whether glucosamine and chondroitin are effective for arthritis. There have been some claims that these supplements can help reduce pain in people living with osteoarthritis (OA). However, high-quality studies show little or no benefit. There are no claims for the effectiveness of glucosamine and chondroitin in other types
of arthritis. 

What is glucosamine?

Glucosamine is a sugar naturally produced by the body. It is one of the building blocks
of cartilage. Cartilage covers and protects the ends of the bones, allowing bones to move smoothly against each other. Glucosamine supplements come in two forms – glucosamine sulfate and glucosamine hydrochloride. Glucosamine supplements are usually made from crab, lobster or shrimp shells, although some supplements are made from a plant form of glucosamine. They are available as tablets or liquid and often in combination with chondroitin.

What is chondroitin?

Chondroitin is also a natural substance found in the body and in cartilage. It is believed that it helps to draw water and nutrients into the cartilage, keeping it spongy and healthy. Chondroitin is available as chondroitin sulfate supplements, which are made from bovine (cow) or shark cartilage.

Why are these supplements supposed to help arthritis?

It is thought that taking glucosamine and/or chondroitin supplements may relieve pain and prevent or slow the breakdown of cartilage in OA.  However, high-quality studies show little or no benefit. Note, most of the studies have looked only at OA of the knee, with very few studies of other joints (for example, hips, hands, back). 

What does the research say?

While there have been some claims that glucosamine and chondroitin, either together or separately, can help to reduce pain in people living with OA, these claims are now being questioned. Evidence around the effectiveness of these supplements has always been mixed. However, recent reviews of this evidence now suggest that studies that show positive results may be of low quality and unreliable. Higher quality, independent studies suggest that glucosamine and chondroitin are no better than placebos (fake pills) at reducing pain or slowing the impacts of OA. As a result of this, while glucosamine and chondroitin remain safe for most people, many doctors no longer recommend these supplements as a way of managing arthritis. 

To date, there is no evidence that these supplements are effective for any other forms of arthritis.

Summary

While the evidence for whether glucosamine and chondroitin will help your arthritis is low, these supplements are considered safe for most people to try. If you want to try these supplements, talk to your doctor or pharmacist about whether they are safe for you.

What is the recommended dose? 

• Glucosamine sulfate: 1500mg per day 
• Glucosamine hydrochloride: 1500mg per day (note, glucosamine sulfate is suggested to be more effective) 
• Chondroitin sulfate: 800 – 1000mg per day 

Different brands contain different amounts of glucosamine and chondroitin. Read the label carefully to see how many tablets you need to take to get the right dose, or ask your pharmacist for advice.

What are the possible risks?

• Shellfish allergy: most glucosamine supplements are made from shellfish, although some made from non-shellfish sources are now available. 
• Bleeding: people taking the blood thinning medicine warfarin should talk to their doctor before starting, stopping or changing their dose of glucosamine or chondroitin. These supplements may interact with warfarin and make the blood less likely to clot or increase the risk of bleeding.
• Diabetes: glucosamine is a type of sugar so check with your doctor before taking glucosamine if you have diabetes.
• Pregnant or breastfeeding women: there have not been enough long-term studies to clearly say that glucosamine is safe for a developing baby. Pregnant women should talk to their doctor before taking glucosamine.
• Other side effects: upset stomach (for example, diarrhoea), headaches, and skin reactions. 

Talk to your doctor or pharmacist about whether you should be trying these medications, whether they are safe for you and, if you decide to try them, make sure you get the right dose.

High-quality evidence shows little or no benefit from glucosamine or chondroitin for OA. If you want to try these supplements, talk to your doctor or pharmacist about whether they are safe for you.

Australian Rheumatology Association and Arthritis Australia Statement regarding the use of glucosamine for the treatment of Osteoarthritis

Recent media reports have raised concern over the use of glucosamine in the treatment of osteoarthritis.  These reports appear to be based on two unrelated recent events:

1. A change in recommendation by the American College of Rheumatology (ACR) [1]

In October 2019 the ACR updated their guidelines for the management of osteoarthritis from a longstanding conditional recommendation against the use of glucosamine for osteoarthritis (on the basis that it probably does not help), to a strong recommendation against the use of glucosamine for osteoarthritis (on the basis that it convincingly does not help).  They did not cite new safety concerns.

2. A recent paper highlighting the known risks associated with glucosamine, particularly in people with shellfish allergy [2]

This paper reviewed 366 glucosamine related adverse drug reactions reported to the Therapeutic Goods Administration between 2000-2011, including 43 classified as severe, possibly related to the known risks of glucosamine in those with shellfish allergy.  This highlights a valid concern but the number of adverse events needs to be considered in the context of the many hundreds of thousands of people who took glucosamine during that period. This suggests that severe adverse reactions are very uncommon.

Many other osteoarthritis treatment guidelines make conditional recommendations against the use of glucosamine on the basis that it probably does not help, including The Royal Australian College of General Practitioners guideline for the management knee and hip OA [3].

Arthritis Australia and Australian Rheumatology Association comment:

This information highlights growing evidence that glucosamine does not help people with osteoarthritis and is a reminder that people with shellfish allergy should not take glucosamine (which is commonly derived from shellfish).  It does not identify any new safety concerns and should not cause undue alarm in people already taking glucosamine.

Comment from The Royal Australian College of General Practitioners (RACGP):

Dr Harry Nespolon, President of the RACGP stated “The RACGP does not recommend the use of glucosamine as a way of preventing osteoarthritis. If you have concerns about using glucosamine or treatment for osteoarthritis I recommend you have a chat with your local GP about the options available to you.”

References:

[1] https://www.rheumatology.org/Portals/0/Files/Osteoarthritis-Guideline-Early-View-2019.pdf

[2] https://www.ncbi.nlm.nih.gov/pubmed/31597786

[3] https://www.racgp.org.au/afp/2015/june/your-questions-about-complementary-medicines-a-1

Media Contacts:

Australian Rheumatology Association – T:  02 9252 2356  E:  [email protected]

Arthritis Australia – T:  02 9518 4441  E:  [email protected]

The Royal Australian College of General Practitioners – T: 03 8699 0939 | E: [email protected]

CONTACT YOUR LOCAL ARTHRITIS OFFICE FOR MORE INFORMATION AND SUPPORT SERVICES.
Websites: Arthritis Research UK ,  Institute of Registered Myotherapists of Australia , Australian Association of Massage Therapists , Australian Acupuncture and Chinese Medicine Association , National Herbalists Association of Australia , Australian Naturopathic Practitioners Association ,  Australian Homeopathic Association , National Center for Complementary and Integrative Health (US).