[Plasma levels and tissue concentrations in rabbits following cutaneous administration of an indomethacin solution]

After cutaneous application to rabbits of a solution containing 1% of indomethacin (Elmetacin), concentration-time curves were determined in the skin-layers, in the subcutaneous tissue, in the superficial musculature, in the knee-joint capsule and in plasma. The quantitative assay used on-line fluorimetric detection after separation by HPLC and alkaline hydrolysis. Levels of indomethacin decreased with the depth of the tissue layers at the site of application. Indomethacin concentrations in the examined tissues exceeded plasma concentration at least twice for up to 8 h. Indomethacin was also detectable in the contralateral untreated tissue specimens and in the knee joint capsule.