Soluble inclusion complex comprising one or several active substances difficult to dissolve in aqueous medium including one or several host molecules and piroxicam-cyclodextrin-arginine in which the level of solubilization of piroxicam in solution containing 4 g/liter piroxicam in water, measured at 37[deg]C with agitation over 5-120 minutes is higher than 90%, most especially higher than 99%. INDEPENDENT CLAIM are included for: (1) preparation of the complex involving:contact with host molecules, initation of molecular diffusion, recovery of the soluble inclusion compound formed； (2) a pharmaceutical composition containing the complex.本發明係關於一種含匹若西卡、環糊精及精胺酸的複合物，其特徵在於含4克/升匹若西卡的水溶液內在攪拌5至120分鐘之後於37℃下測定的溶解度係大於90%，較佳為大於95%，更佳為等於99%。；本發明亦係關於一種用於製備此複合物的方法，以及其治療上的用途。
