Dissolution and Transformation of Crystal Forms of Piroxicam

피록시캄 결정형의 용출과 형전환

The polymorphism of piroxicam was studied. Form I, II, III and monohydrate designated as Form IX were prepared by recrystallization from different solvents. Depending on the coo ling rate of the piroxicam melt, Form IV, V, VI, VII and VIII were prepared. The crystal forms were characterized by DTA, TGA and UV spectroscopy. Their dissolution patterns were also investigated. During storage at ambient condition. Form VIII was transformed into Form I and it was accelerated by milling. The other crystal forms were also transformed into Form I by milling. Form I and Form IX were very stable.