BIOAVAILABILITY STUDIES OF THEOPHYLLINE MICROCAPSULES

Document Type : Original Article

Authors

Department of Pharmaceutics, Faculty of Pharmacy, Assiut University, Assiut, Egypt

Abstract

The release of theophylline from microcapsules prepared by using different concentrations of ethylene-vinyl acetate (EVA) copolymer as a coacervation-inducing agent was investigated in simulated gastric and intestinal fluids. Also the bioavailability of theophylline from its microcapsules following oral administration in volunteers using the saliva drug concentration was investigated.
The results pointed out that the higher the concentration of EVA compolymer used the more sustainment of theophylline from microcapsules. The investigation painted for a good correlation between the in-vitro release rate characteristics and the in-vivo salivary bioavailability parameters of theophylline microcapsules. The prepared theophylline microcapsules were proven to achieve excellent sustainment pattern and could be used to avoid sub-/or/super therapeutic levels of conventional theophylline products.