Yet the findings will also lend scientific weight to earlier sometimes conflicting evidence on the efficacy of this natural supplement, both alone and in combination with chondroitin sulphate.
The first set of results come from the multi-centered Glucosamine/chondroitin Arthritis Intervention Trial (GAIT) conducted by the US government-funded National Institutes of Health.
Almost 1,500 osteoarthritis patients were given a daily dose of either 1,500 mg of glucosamine hydrochloride, 1,200 mg of chondroitin sulphate, a combination of both supplements, 200 mg of the common prescription painkiller celecoxib (Celebrex) or a placebo for 24 weeks.
The patients were evaluated at baseline and every four weeks thereafter.
Both celecoxib and the glucosamine-chondroitin combination significantly reduced knee pain compared to placebo.
“Combination glucosamine and chondroitin sulphate is effective in treating moderate to severe knee pain due to osteoarthritis,” says the authors’ abstract.
It adds that a lack of response in patients with mild pain may be due to a floor effect, limiting ability to detect response.
Daniel Clegg from the University of Utah will present the full study findings at the American College of Rheumatology (ACR) meeting in San Diego on 14 November.
The following day Dr Herrero-Beaumont from the Fundacion Jimenez Diaz in Madrid will disclose the results of a multi-centre European study, which has found glucosamine sulphate to be more effective than the over-the-counter painkiller acetaminophen on joint pain.
The Glucosamine Unum in Die Efficacy (GUIDE) trial compared a daily dose of 1500mg of glucosamine sulphate and 3000 mg of the OTC drug to a placebo in 318 patients.
Steve - as effective as we know it is, glucosamine is not for everyone. For those with shellfish, salicylate or sulfa sensitivity, it is poison. Also, keep in mind that it is partially a "band-aid' approach. As usual, nothing replaces diet as the gold standard for pain relief. Although, it is a much better choice than NSAID's and COX-1 or 2 inhibitors.