Using the Dissolution Test to Evaluate the Quality of Theophylline Extended-Release Tablets

Abstract 【Background】 Promoting the use of generic preparations is an important means to curtail increasing medical costs. However, anxiety regarding the quality of generic preparations inhibits their use. In this study, we compared the quality of brand name and generic theophylline extended-release tablets by examining their dissolution profiles. The purpose of this study was to determine which generic preparations the pharmacist should recommend as an alternative to the brand preparation, thereby contributing to patients’ safety. 【Methods】 The dissolution profile of theophylline from generic theophylline extended-release tablets was tested and compared to that of the brand preparation. Two or three lots per preparation of nine preparations were tested. Each tablet contained 100 mg theophylline. 【Results】 The dissolution profiles were grouped into four types based on their dissolution in water. Some tablets showed slight variance between lots. When assessing similarities between the dissolution profiles, in some cases we could not distinguish between the generic and the brand preparation found in the Orange Book. 【Conclusion】 When pharmacists select a generic preparation for a patient, it is important to consider the dissolution profile of the brand name preparation because dissolution profiles vary among tablets. Although theophylline extended-release tablets can be divided into groups based on the dissolution profile in the Orange Book, it seems that there are slight differences in dissolution profiles within the same group under different patient conditions. Pharmacists should consider the patient’s condition when changing from the brand preparation to a generic preparation.