[Pellet technology. Sustained-release pellets in hard gelatin capsules--a suitable dosage form for theophylline]

Reproducible gastrointestinal transit times of multiple unit dosage forms result in increasing efficacy and safety of pellets compared to single unit dosage forms. Furthermore, predictable concentration/time profiles can be achieved and local mucosa irritations can be avoided. These pharmacokinetic and clinical advantages compensate the increased investment necessary for development and production of theophylline (CAS 58-55-9) sustained release dosage forms. Several process steps are necessary to obtain the finished dosage form. After manufacturing, the pellet cores are coated and encapsulated in hard gelatine capsules. Manufacturing based on pelletization in an intensive mixer followed by drying of the pellet cores in a fluid-bed dryer and filmcoating according to the direct current principle in a Kugelcoater has become an established manufacturing technology both economically and ecologically.