Articles

Effects of a ginger extract on knee pain in patients with osteoarthritis

Author

Altman RD, Marcussen KC

Date

11/2001

Journal

Arthritis Rheum

Abstract

OBJECTIVE: To evaluate the efficacy and safety of a standardized and highly concentrated extract of 2 ginger species, Zingiber officinale and Alpinia galanga (EV.EXT 77), in patients with osteoarthritis (OA) of the knee. METHODS: Two hundred sixty-one patients with OA of the knee and moderate-to-severe pain were enrolled in. After washout, patients received ginger extract or placebo twice daily, with acetaminophen allowed as rescue medication. The primary efficacy variable was the proportion of responders experiencing a reduction in "knee pain on standing," using an intent-to-treat analysis. A responder was defined by a reduction in pain of > or = 15 mm on a visual analog scale. RESULTS: In the 247 evaluable patients, the percentage of responders experiencing a reduction in knee pain on standing was superior in the ginger extract group compared with the control group (63% versus 50%; P = 0.048). Analysis of the secondary efficacy variables revealed a consistently greater response in the ginger extract group compared with the control group, when analyzing mean values: reduction in knee pain on standing (24.5 mm versus 16.4 mm; P = 0.005), reduction in knee pain after walking 50 feet (15.1 mm versus 8.7 mm; P = 0.016), and reduction in the Western Ontario and McMaster Universities osteoarthritis composite index (12.9 mm versus 9.0 mm; P = 0.087). Change in global status and reduction in intake of rescue medication were numerically greater in the ginger extract group. Change in quality of life was equal in the 2 groups. Patients receiving ginger extract experienced more gastrointestinal (GI) adverse events than did the placebo group (59 patients versus 21 patients). GI adverse events were mostly mild. CONCLUSION: A highly purified and standardized ginger extract had a statistically significant effect on reducing symptoms of OA of the knee. This effect was moderate. There was a good safety profile, with mostly mild GI adverse events in the ginger extract group.