Glassy state of pharmaceuticals. II. Bioinequivalence of glassy and crystalline indomethacin.

Bioinequivalence of glassy and crystalline indomethacin was investigated in rabbits. In vivo absorption studies were carried out by determining the plasma levels of indomethacin following oral and rectal administrations in rabbits. The A UC (area under the concentration–time curve) and the maximum plasma level following the administration of the glassy preparation were larger than those in the case of the crystalline preparation. The amounts of indomethacin absorbed were calculated by the deconvolution method. It was shown that the amounts absorbed following oral and rectal administrations of the glassy preparation were larger than those in the case of the crystalline preparation. These results indicated that the bioavailability of the glassy indomethacin was better than that of the crystalline indomethacin.