Skip to main content

Glucosamine and Chondroitin for Osteoarthritis: What You Need To Know

pills vitamins supplements_chondroitin.

What is osteoarthritis?

Osteoarthritis is a degenerative joint disease in which cartilage and other tissues within the joint break down or change in structure. Symptoms can include pain, joint stiffness, swelling, and difficulty in moving the joint. The joints most frequently affected by osteoarthritis include the knees, hips, and hands.


There is no cure for osteoarthritis, but a variety of treatments and self-management strategies (such as losing weight and increasing physical activity) can help people manage symptoms.

More than 32 million adults in the United States have osteoarthritis. The risk increases with age. Joint injury, obesity, and a family history of osteoarthritis also increase risk.

What are glucosamine and chondroitin?

Glucosamine and chondroitin are constituents of cartilage, a component of the joints. Glucosamine is a building block for molecules called glycosaminoglycans that are part of the structure of cartilage. Chondroitin is a component of cartilage that plays a role in its resistance to compression.

Glucosamine (as either glucosamine sulfate or glucosamine hydrochloride) and chondroitin (as chondroitin sulfate) are sold in the United States as dietary supplements, separately or together. In some other countries, certain preparations of glucosamine and chondroitin are sold as prescription drugs. In a 2017 U.S. survey, chondroitin (with or without glucosamine) was the dietary supplement most commonly used by people age 35 and older who had been diagnosed with osteoarthritis.

Are glucosamine and chondroitin helpful for symptoms of knee osteoarthritis?

There has been a substantial amount of research on the use of glucosamine and chondroitin, separately or together, for pain and joint function in people with knee osteoarthritis, but studies have had inconsistent results, and expert evaluations of the evidence have reached conflicting conclusions. It’s still uncertain whether glucosamine and chondroitin are helpful for knee osteoarthritis symptoms.


A 2018 combined analysis of 29 studies in people with knee osteoarthritis (6,120 total participants) showed that global pain was significantly reduced by glucosamine or chondroitin taken separately but not by the combination of the two. The results of individual studies were inconsistent; some pointed to significant benefits, while others did not.


A 2014 analysis of 25 studies of glucosamine taken alone for knee osteoarthritis (3,458 participants) showed a pattern in the results of individual studies: those who used the prescription drug formulation of glucosamine generally had more favorable results than those who did not. This pattern may reflect genuine differences in the effects of different products, but it could also be a result of bias. Most of the studies of the prescription drug formulation had a high risk of bias because of weaknesses in their study design, were published more than 20 years ago, and were funded by the pharmaceutical company.

Clinical practice guidelines issued by health professional organizations in the United States and other countries differ in their recommendations concerning glucosamine. The guideline published by the American College of Rheumatology (ACR) and the Arthritis Foundation (AF) in 2019 strongly recommended against the use of glucosamine alone or in combination with chondroitin for knee osteoarthritis, stating that the best data do not show any important benefits. Similarly, a 2019 guideline from Osteoarthritis Research Society International (OARSI) strongly recommends against the use of glucosamine for knee osteoarthritis on the grounds of lack of efficacy.

In contrast, the 2021 guideline from the American Academy of Orthopaedic Surgeons (AAOS) includes glucosamine in a list of dietary supplements that may be helpful in reducing pain and improving function in patients with mild-to-moderate knee osteoarthritis, although it cautions that the evidence is inconsistent. A 2019 statement from the European Society for Clinical and Economic Aspects of Osteoporosis, Osteoarthritis and Musculoskeletal Diseases (ESCEO) strongly recommends prescription crystalline glucosamine sulfate for knee osteoarthritis but discourages the use of other glucosamine formulations.


A 2019 analysis of 18 studies of chondroitin taken alone for osteoarthritis (3,791 participants), 16 of which were on knee osteoarthritis, showed a significant benefit of chondroitin, but with much inconsistency in the study results. When only studies with a low risk of bias were included in the analysis, there was a significant difference among brands of chondroitin, with a specific pharmaceutical grade preparation showing a greater reduction in pain.

Clinical practice guidelines differ in their recommendations about chondroitin. The 2019 ACR/AF guideline strongly recommends against the use of chondroitin alone or in combination with glucosamine for knee osteoarthritis, and the 2019 OARSI guideline strongly recommends against the use of chondroitin for knee osteoarthritis on the grounds that the evidence is of low quality. However, the 2021 AAOS guideline includes chondroitin in a list of dietary supplements that may be helpful in reducing pain and improving function in patients with mild-to-moderate knee osteoarthritis, although it cautions that the evidence is inconsistent, and the 2019 ESCEO statement strongly recommends prescription chondroitin sulfate for knee osteoarthritis and says that it should be distinguished from other chondroitin products.

Do glucosamine and chondroitin have effects on joint structure in knee osteoarthritis?

Because glucosamine and chondroitin are components of cartilage, it has been suggested that they might have an impact on joint structure in osteoarthritis, which may be assessed by looking at changes in joint space. Whether glucosamine and chondroitin actually have an effect on joint structure is uncertain. Studies have had inconsistent results.


Two large 2-year trials of glucosamine and chondroitin for knee osteoarthritis, one in Australia and one in the United States, produced conflicting results for effects on joint space. 

  • The Australian study, published in 2015, included 605 participants who received glucosamine sulfate, chondroitin, both glucosamine and chondroitin, or a placebo for 2 years. The group that received both glucosamine and chondroitin showed a reduction in joint space narrowing. No reduction in joint space narrowing was seen in the groups that received glucosamine alone or chondroitin alone.
  • The U.S. study, published in 2008, included 572 participants who received glucosamine hydrochloride, chondroitin, both glucosamine and chondroitin, the drug celecoxib, or a placebo for 2 years. Changes in joint space width did not differ between the placebo group and any of the other groups.

Two additional 2-year studies that looked at chondroitin alone, one with 622 participants and one with 300 participants, found improvements in joint space in people who were taking chondroitin compared with those taking placebo. However, these findings conflict with those of the Australian and U.S. studies described above, neither of which found a beneficial effect for chondroitin alone.

Are glucosamine and chondroitin helpful for osteoarthritis in other joints?

There is only a small amount of evidence on glucosamine or chondroitin for osteoarthritis in joints other than the knee. Joints that have been studied include the hip, hand, and temporomandibular joint (the joint that connects the jaw to the side of the head, which is involved in talking, chewing, and yawning).

Hip Osteoarthritis

In 2017, the American Academy of Orthopaedic Surgeons published a clinical practice guideline on management of osteoarthritis of the hip that concluded that moderate strength evidence does not support the use of glucosamine sulfate for hip osteoarthritis. This conclusion was based on the one high-quality study that was identified. This study, published in 2008, included 222 participants, who received 2 years of treatment with glucosamine sulfate or a placebo. Glucosamine was no better than placebo in terms of effects on pain, joint function, or joint structure (assessed as joint space narrowing).

Hand Osteoarthritis

One study with 162 participants has evaluated chondroitin for hand osteoarthritis. In this 6-month trial, hand pain decreased and hand function improved to a greater extent in the chondroitin group than the placebo group. 

The 2019 guideline for osteoarthritis management from the American College of Rheumatology and the Arthritis Foundation conditionally recommends chondroitin for patients with hand osteoarthritis.

Temporomandibular Joint Osteoarthritis

A review of 8 studies (538 participants) of glucosamine for temporomandibular joint osteoarthritis was unable to reach definite conclusions about whether glucosamine supplements are helpful for symptoms of this condition. The studies were difficult to compare because they used different methods and different types of glucosamine, and some studies may have been biased. The reviewers did conclude, however, that use of glucosamine for 3 months or more led to reduced pain and improvement in maximum mouth opening.

Are glucosamine and chondroitin safe?

No major safety problems have been identified in large studies of glucosamine and chondroitin for osteoarthritis. However, glucosamine may cause increases in blood glucose (sugar) levels in some people, and glucosamine and chondroitin have been associated with an increased risk of bleeding in people who are taking the anticoagulant warfarin. Little is known about the safety of using glucosamine and chondroitin during pregnancy or while breastfeeding.

For More Information

NCCIH Clearinghouse

The NCCIH Clearinghouse provides information on NCCIH and complementary and integrative health approaches, including publications and searches of Federal databases of scientific and medical literature. The Clearinghouse does not provide medical advice, treatment recommendations, or referrals to practitioners.

Toll-free in the U.S.: 1-888-644-6226

Telecommunications relay service (TRS): 7-1-1


Email: (link sends email)

Know the Science

NCCIH and the National Institutes of Health (NIH) provide tools to help you understand the basics and terminology of scientific research so you can make well-informed decisions about your health. Know the Science features a variety of materials, including interactive modules, quizzes, and videos, as well as links to informative content from Federal resources designed to help consumers make sense of health information.

Explaining How Research Works (NIH)

Know the Science: How To Make Sense of a Scientific Journal Article

Understanding Clinical Studies (NIH)


A service of the National Library of Medicine, PubMed® contains publication information and (in most cases) brief summaries of articles from scientific and medical journals. For guidance from NCCIH on using PubMed, see How To Find Information About Complementary Health Approaches on PubMed.


Key References

Other References

  • Chondroitin. Drugs and Lactation Database. (LactMed). National Institute of Child Health and Human Development. Updated May 2021. Accessed at on June 20, 2023.
  • Glucosamine. Drugs and Lactation Database. (LactMed). National Institute of Child Health and Human Development. Updated May 2021. Accessed at on June 20, 2023.
  • Hatfield J, Saad S, Housewright C. Dietary supplements and bleeding. Proceedings (Baylor University, Medical Center). 2022;35(6):802-807.
  • Hochberg MC. Structure-modifying effects of chondroitin sulfate in knee osteoarthritis: an updated meta-analysis of randomized placebo-controlled trials of 2-year duration. Osteoarthritis and Cartilage. 2010;18:S28-S31.
  • MedlinePlus. Temporomandibular Joint Dysfunction. Accessed at on July 18, 2023.
  • Wandel S, Jüni P, Tendal B, et al. Effects of glucosamine, chondroitin, or placebo in patients with osteoarthritis of hip or knee: network meta-analysis. BMJ. 2010;341:c4675.


NCCIH thanks D. Craig Hopp, Ph.D., and David Shurtleff, Ph.D., NCCIH, for their review of the 2023 update of this fact sheet.

This publication is not copyrighted and is in the public domain. Duplication is encouraged.

NCCIH has provided this material for your information. It is not intended to substitute for the medical expertise and advice of your health care provider(s). We encourage you to discuss any decisions about treatment or care with your health care provider. The mention of any product, service, or therapy is not an endorsement by NCCIH.

Last Updated: October 2023