Glucosamine is naturally occuring sugar in the body, and one of “building blocks” of cartilage. Most tablets are made from crab, lobster or shrimp shells-hence caution required if people have shellfish allergies. May also interact with warfarin and diabetes.
Often taken in combination with chondroitin.
Overall very low quality evidence found small short term benefit, no long term benefit.
No apparent benefit has been found with function, quality of life or joint space narrowing.
RACGP OA Guidelines state: “If someone who is taking glucosamine or chondroitin is feeling marked symptomatic benefit as a consequence of its consumption, it is appropriate not to discourage whatever placebo effects may come from use of these supplements.”
RACGP OA Guideline: Conditional against recommendation (recommend not offering)
Chondroitin is found in connective tissues and bone and is thought to help draw water and nutrients to cartilage. Often comes as Chondroitin sulfate and can be tablet or power; usually made from cow or shark cartilage.
Low quality studies found short term benefit, however no benefit in high quality or non-industry sponsored trials.
RACGP OA Guidelines state: “If someone who is taking glucosamine or chondroitin is feeling marked symptomatic benefit as a consequence of its consumption, it is appropriate not to discourage whatever placebo effects may come from use of these supplements.”
RACGP OA Guideline: Conditional against recommendation (recommend not offering)
Tumeric or curcumin is an Indian spice with anti-inflammatory and anti-rheumatic effect, although poor absorbability. It is thought have an effect on OA via reducing inflammatory mediators, as well as having anti-oxidative and anti-catabolic properties.
Liu et al.’s systematic review reported a large and clinically meaningful effect on pain for OA patients, although this was with low quality evidence from only two trials using different preparations and dosages.
Curcumin may have an anti-coagulant effect, as well as possible interactions with other medication including anti-coagulants. Currently there’s insufficient evidence to determine the safety of use although the two RCTs in Liu’s systematic review did not report any serious adverse events.
RACGP OA guidelines gives a neutral (unable to recommend for or against) recommendation, as does OARSI 2019 guidelines
Fish oil, Krill oil and Green-lipped mussel extract are the most common omega-3 fatty acids supplements .
Treatment effects on pain were reported as inconclusive for fish oil and krill oil, and mixed for green-lipped mussel extract (previous positive results vs placebo although recent RCT didn’t support these findings.
Side effects reported in trials include GI upset, dry skin, epigastric discomfort, nausea.
The effect of fish oil supplements on pain and function in people with OA is inconclusive
RACGP OA guidelines have a conditional against recommendation
Courtesy of Professor David Hunter’s Joint Action Podcasts: What supplement should I take?
A 2014 Cochrnae review reported small and clinically questionable improvements compared to placebo after 3 to 12 months. No signficant benefit was noted in longer temr in teh RACGP guidelines.
RACGP guidelines give a NEUTRAL recommendation