The present invention provides a medicinal composition capable of preventing a decrease in the blood exposure level of a third generation coxib drug a method for preparing the composition and utilization of the same. It was discovered that by adding a basic amine or a basic amino acid or cyclodextrin to a third generation coxib compound a medicinal composition capable of inhibiting a decrease in the blood concentration thereof a decrease in the area under concentration thereof and a decrease in the bioavailability thereof can be obtained. In addition the medicinal composition according to the present invention is highly stable and useful as a medicine. That is a technical idea that a decrease in blood concentration a decrease in area under concentration and a decrease in bioavailability can be inhibited by adding a basic amine or a basic amino acid or cyclodextrin is thus established.
