Anti-inflammatory activity of piroxicam after oral and topical administration on an ultraviolet-induced erythema model in man

The efficacy of piroxicam administered both topically (1% cream) and after a single oral dose of 20 mg (capsules) compared with a placebo vehicle was evaluated using a standardized ultraviolet-induced erythema model. The study was carried out with six normal healthy subjects, a double-blind, double-dummy, crossover design with randomized assignment of treatments to the irradiated areas. Subjects received oral piroxicam or placebo and the corresponding topical formulation with a one-week interval between each session. Anti-inflammatory effects were evaluated by measuring the erythema area after ultraviolet-injury on different sites of the subject's back at 4, 6, 7, 8 and 24 hours post-irradiation. The results showed that both active treatments reduced the erythema size. However, the topical application produced a significantly higher inhibition of the irradiated surface, over eight hours, than the oral treatment.