An improvement in the dissolution of theophylline with beta-cyclodextrin was achieved by subjecting them to co-grinding and freeze-drying methods. The products obtained were examined by the phase solubility method, differential scanning calorimetry and X-ray diffractometry. The products thus prepared were evaluated with respect to their dissolution behaviour and particle sizes, and compared with the pure drug and the physical mixture of theophylline and beta-cyclodextrin. The improvement in the dissolution profile of theophylline in the interacted form may be due to its amorphous state, to increased wettability, or to the formation of an inclusion complex.

WOS: A1994NG07800006