A prescription drug cleared the bar; the supplements did not
Across 1,583 people over 24 weeks, six in ten on placebo hit the target of a fifth less knee pain. Neither supplement nor the pair beat that. Celecoxib did.
What the study found
Celecoxib beat placebo in the biggest trial; the supplements did not
The placebo did most of the work. Across 1,583 people over 24 weeks, six in ten on placebo reached the trial's target of a fifth less knee pain. Glucosamine, chondroitin and the two combined all failed to clear that bar. Celecoxib, a prescription anti-inflammatory, cleared it.
The caveat · Everyone could take paracetamol too
A placebo response of six in ten leaves very little room for a supplement to show a difference, and every arm could take up to 4,000 mg of paracetamol a day as rescue, narrowing the gaps further. The trial used glucosamine hydrochloride, not the sulfate salt sold in Europe as a medicine.