Assessment of topical non-steroidal anti-inflammatory drugs.

A new non-invasive technique for assessing the efficacy of topical non-steroidal anti-inflammatory drugs (NSAID) in man is proposed. The NSAID are initially applied to the skin under occlusion before inflammation is induced by a methyl nicotinate solution. The inflammatory response is quantified in terms of cutaneous blood flow by a laser Doppler velocimeter (LDV). The efficacy of NSAID preparations is calculated by comparing the responses of the LDV to the methyl nicotinate challenge on the pretreated and the non-treated skin sites. This protocol has been used to investigate the effect of three different NSAID preparations (indomethacin, niflumic acid, palmitoyl collagenic acid) and the influence of the vehicle on the efficacy of indomethacin. The three preparations tested gave positive results but with different amplitudes in response. The efficacy of indomethacin varied with the vehicle used.