Objective: To determine the effectiveness of glucosamine in reducing pain from osteoarthritis of the knee.
Design: Randomized, double-blind parallel trial of glucosamine 500 mg three times daily or a placebo for 2 months.
Setting: Veterans Affairs Medical Center, Prescott, AZ.
Participants: Ninety-eight patients aged 34 to 81 being treated for osteoarthritis of the knee.
Main outcome measures: Pain intensity both at rest and while walking as assessed by a visual analog scale at baseline and after 30 and 60 days of treatment.
Results: Forty-nine patients were randomly allocated to each group. There was no statistical difference between the two groups in scores on the visual analog scale at 30 days for resting (mean [SD] score placebo group 3.5 [2.7] vs 3.3 [2.4] glucosamine group, P = 0.66) or walking (5.1 [2.6] vs 5.3 [2.4], P = 0.69); there was also no difference at 60 days for resting (3.4 [2.5] vs 3.2 [2.5], P = 0.81) or walking (4.9 [2.2] vs 4.9 [2.8], P = 0.90). There was also no statistical difference between groups in the mean change from baseline in scores on the visual analog scale (mean [SD] change for walking at 60 days placebo group -1.5 [2.5] vs glucosamine group -1.4 [3.0], P = 0.77). Two participants taking glucosamine and 4 taking placebo withdrew from the study due to adverse side effects (P = 0.67).
Conclusion: Glucosamine was no better than placebo in reducing pain from osteoarthritis of the knee in this group of patients.