Quantitative assessment of markers of inflammation, arthritis and pain in rats with adjuvant arthritis following the treatment with ibuprofen cream and placebo.

When applied topically, nonsteroidal antiinflammatory drugs (NSAIDs) are absorbed locally and hence systemic adverse effects can be avoided due to very low plasma concentrations. In addition, direct local antiphlogistic treatment of the affected area is desirable. The present study was undertaken to assess markers of inflammation, arthritis and pain in rats with adjuvant arthritis undergoing treatment with ibuprofen cream (Dolgit cream) and placebo. Ibuprofen cream was applied (70 mg/hind paw) 3 times daily on hind paws from day 12 (after the initial signs of hind paw swelling appeared) for 3 weeks. Pain threshold, hind paw swelling, arthrogram score and serum albumin concentrations were measured in healthy controls, in rats with adjuvant arthritis and in rats treated with both placebo and active cream. Pain threshold increased in rats treated with ibuprofen cream (after 12 days of application), but this change was not significant. However, hind paw swelling significantly decreased as early as after 5 days of treatment with ibuprofen cream in comparison with both arthritic and placebo-treated rats and remained decreased throughout the study (an additional 16 days). Evaluation of the arthrogram score gave similar results. Serum albumin levels were unaffected by ibuprofen cream treatment. In conclusion, our results show that topical application of ibuprofen cream on inflamed hind paws produced significant local antiinflammatory and antiarthritic effects in rat adjuvant arthritis.