A randomized, placebo-controlled, cross-over study of ginger extracts and Ibuprofen in osteoarthritis

Objective: Alternative medicine is used extensively by patients with chroni c pain due to e.g., osteoarthritis. Only few of these drugs have be tested in a controlled setting and the present study was undertaken to examine the effect of ginger extract, one of the most popular herbal medications. Design: Ginger extract was compared to placebo and Ibuprofen in patients wi th osteoarthritis of the hip or knee in a controlled, double blind, double dummy, cross-over study with a wash-out period of one week followed by thre e treatment periods in a randomized sequence, each of three weeks duration. Acetaminophen was used as rescue medication throughout the study. The stud y was conducted in accordance with Good Clinical Practice (European Guideli ne for GCP). Results: A ranking of efficacy of the three treatment periods: Ibuprofen>gi nger extract>placebo was found for visual analogue scale of pain (Friedman test: 24.65, P<0.00001) and the Lequesne-index (Friedman test: 20.76, P<0.0 0005). In the cross-over study, no significant difference between placebo a nd ginger extract could be demonstrated (Siegel-Castellan test), while expl orative tests of differences in the first treatment period showed a better effect of both Ibuprofen and ginger extract than placebo (Chi-square, P<0.0 5). There were no serious adverse events reported during the periods with a ctive medications. Conclusion: In the present study a statistically significant effect of ging er extract could only be demonstrated by explorative statistical methods in the first period of treatment before cross-over, while a significant diffe rence was not observed in the study as a whole. (C) 2000 OsteoArthritis Res earch Society International.