Table 1: Studies on the effectiveness of Glucosamine for Osteoarthritis.

Author [reference]Sample and/or amount of trialsSupplement type, dosesConclusions

Reginster et al. [63]Patients treated with GS: 106, placebo: 106GS (1500 mg OD)In this randomized, double-blind placebo-controlled trial, treatment with GS prevented loss of articular space and improved symptoms as assessed by WOMAC scoring at a 3-year follow-up.

Pavelká et al. [64]Patients treated with GS: 101, placebo: 101GS (1500 mg OD)This randomized, double-blind placebo-controlled trial also found treatment with GS to prevent loss of articular space and ameliorate pain as assessed by WOMAC scoring and the Lequesne Index at a 3-year follow-up.

Bruyere et al. [65]Patients treated with GS: 144, placebo: 131GS (1500 mg OD)This placebo-controlled prospective study suggests that treatment with GS for at least 12 months and up to 3 years may prevent the need to perform knee arthroplasty in an average follow-up of 5 years after drug discontinuation.

Herrero-Beaumont et al. [66]Patients treated with GS: 106, acetaminophen: 108, placebo: 104GS (1500 mg OD), acetaminophen (3 g OD)In this randomized, double-blind, placebo-controlled study, daily consumption of 1500 mg of GS proved more effective than placebo in the symptomatic management of knee OA. Nonetheless, the effects of acetaminophen were similar.

Clegg et al. [67]Patients treated with GH: 317, CS: 318, GH + CS: 317, celecoxib: 318, Placebo: 313GH (1500 mg OD)In this randomized, double dummy study, neither treatment with glucosamine alone nor combined with CS reduced pain in the average OA patient group during 24 weeks. However, combined therapy may be effective in the group of patients with moderate to severe knee pain.

McAlindon et al. [68]15 randomized, double-blind, placebo-controlled trials with ≥4 weeks of treatmentGS, GH, or SC versus PlaceboIn this meta-analysis, trials indicate these compounds have a moderate to strong effect over OA symptoms, but methodology issues may exaggerate this beneficial effect. Notwithstanding this, they appear to be safe and have a positive impact over symptomatology.

Towheed et al. [31]25 randomized, controlled trials (4963 patients)GS (1500 mg OD)This meta-analysis suggests that GS preparations by Rotta Laboratories may be more effective than placebo in the management of pain and articular functionality as assessed by the Lequesne Index in subjects with symptomatic OA Nevertheless, other formulations did not show any effectiveness (statistical significance) at managing pain nor functionality or rigidity as assessed by the WOMAC scale.

Wandel et al. [69]10 large scale randomized placebo-controlled trials (3803 patients)GS, GH, or SC versus placeboThis meta-analysis suggests neither glucosamine nor chondroitin alone, nor their combination, is able to reduce articular pain, nor can they modify articular space in comparison to placebo.

OD: once daily; GS: glucosamine sulfate; CS: chondroitin sulfate; OA: osteoarthritis; GH: glucosamine hydrochloride.