Chondroitin
Summary
Chondroitin sulfate is a building block of cartilage sold for osteoarthritis. Results depend on trial quality: a Cochrane review found modest short-term pain relief from mostly small, high-risk trials, while large, rigorous trials such as GAIT found little or no benefit. Side effects were similar to placebo.
Key facts
- A component of cartilage that helps it resist compression; sold in the US as chondroitin sulfate supplements, alone or with glucosamine[4]
- Cochrane (43 RCTs): pain about 10 points lower on a 0–100 scale in trials under 6 months, low-quality evidence with high heterogeneity[1]
- The 3 large, rigorously analysed trials: effect size −0.03, about 0.6 mm on a 10 cm pain scale[3]
- 1,200 mg/day for 24 weeks was not significantly better than placebo for knee pain in 1,583 people[2]
- Adverse events similar to placebo (pooled relative risk 0.99)[3]
- The 2019 American College of Rheumatology/Arthritis Foundation and OARSI guidelines strongly recommend against chondroitin for knee osteoarthritis; ACR conditionally recommends it for hand osteoarthritis[4]
- 3 graded human outcomes on this page
- October 11, 2026
How it works
ProposedChondroitin is proposed to slow cartilage breakdown and reduce joint inflammation; how oral chondroitin might act in people is not established.[1]
What the human research says
Human trials only, one row per outcome. The form column shows what each trial actually tested. Grades follow our evidence-grading policy.
| Outcome | Effect | Grade | Best evidence | PMID |
|---|---|---|---|---|
| Osteoarthritis pain (20% reduction, WOMAC) | Improved | Grade B | Systematic review · n = 1,253 · 2015 Adults with knee osteoarthritis in the 2 low-risk-of-bias trials pooled for this outcome Form: Chondroitin sulfate · Dose: Varied across trials · Duration: 1 month to 3 years across the review 53 of 100 on chondroitin versus 47 of 100 on placebo reached a 20% drop in knee pain (high-quality evidence); across all 43 trials pain scores were 10 points lower in short trials, but with low-quality, heterogeneous evidence. | 25629804 (opens PubMed)Source [1] |
| Osteoarthritis pain (knee or hip) | Mixed | Grade C | Meta-analysis · n = 3,846 · 2007 Adults with knee or hip osteoarthritis in 20 trials Form: Chondroitin · Dose: Varied across trials · Duration: Varied across trials Heterogeneity was very high (I² 92%); small and lower-quality trials showed larger benefits, and the 3 large intention-to-treat trials showed essentially no effect. | 17438317 (opens PubMed)Source [3] |
| Knee pain response (20% drop) | No effect | No effect | RCT · n = 1,583 · 2006 Adults with symptomatic knee osteoarthritis (mean age 59) Form: Chondroitin sulfate, alone or with glucosamine · Dose: 1,200 mg/day chondroitin (with or without 1,500 mg/day glucosamine) · Duration: 24 weeks Response was 5.3 points higher than placebo for chondroitin alone (P=0.17) and 6.5 points for the combination (P=0.09), both not significant; celecoxib beat placebo. An exploratory moderate-to-severe pain subgroup did better on the combination. | 16495392 (opens PubMed)Source [2] |
Forms
| Form | Elemental % | Absorption (human data) | GI tolerance | Studied for |
|---|---|---|---|---|
| Chondroitin sulfate | Varies | No head-to-head human absorption data in the sources cited here. | Adverse events similar to placebo in pooled trials.[3] | Knee and hip osteoarthritis trials |
Studied doses
Doses studied in human trials ranged from the 1,200 mg per day used in the GAIT trial to varied doses in the Cochrane trials, which lasted from 1 month to 3 years.[2][1]
Interactions
Published interactions only: each row cites a source. No row means none was found in our sources, not that a combination is safe.
Medicines
- WarfarinNIH fact sheetGlucosamine and chondroitin have been associated with an increased risk of bleeding in people taking warfarin.[4]
Who should be careful
- Pregnancy and breastfeeding
- Little is known about safety in pregnancy or breastfeeding.[4]
- People expecting large pain relief
- Large, rigorous trials found minimal or no benefit over placebo.[3][2]
- People taking warfarin
- NCCIH notes a link between glucosamine and chondroitin and higher bleeding risk with warfarin.[4]
Talk to your pharmacist or clinician before starting a supplement, especially if you take prescription medicines.
Frequently asked questions
Does chondroitin work for knee pain?
It depends on which trials you trust: small, lower-quality trials show benefit, while large rigorous trials such as GAIT show little or none.[3][2]
Is chondroitin better with glucosamine?
In GAIT the combination was not significantly better than placebo overall; an exploratory subgroup with moderate-to-severe pain did better.[2]
Is chondroitin safe?
Pooled trials found adverse events similar to placebo.[3]
How much chondroitin was studied?
GAIT used 1,200 mg per day for 24 weeks.[2]
Sources
- [1]Chondroitin for osteoarthritis. Cochrane Database Syst Rev, 2015. systematic-review
- [2]Glucosamine, chondroitin sulfate, and the two in combination for painful knee osteoarthritis. N Engl J Med, 2006. RCT
- [3]Meta-analysis: chondroitin for osteoarthritis of the knee or hip. Ann Intern Med, 2007. meta-analysis
- [4]Glucosamine and Chondroitin for Osteoarthritis: What You Need To Know. National Center for Complementary and Integrative Health (NCCIH), 2023. fact-sheet
What changed
- New monograph. Every PMID checked against NCBI E-utilities (title, journal and year from the PubMed record); each evidence row written from its abstract; intake and safety facts from the cited fact sheets.
- Review: added the NCCIH warfarin bleeding interaction and guideline positions; removed unsourced animal/marine source wording.