Objectives: In this study, we examined the taste and dissolution of theophylline extended-release dry syrups using one branded and six generic formulations. Methods: Healthy volunteers underwent sensory testing to assess the syrup taste. Drug dissolution was examined using in vitro dissolution tests. Results and discussion: Syrup taste, including sweetness, bitterness, and aftertaste, was different between formulations. These differences can likely be attributed to the presence of different pharmaceutical additives between formulations. Our results indicated that syrup aftertaste was dependent on the level of sweetness and bitterness. In addition, dissolution behaviors were different between formulations, suggesting bio-inequivalence between formulations. These differences likely reflect the use of different controlledrelease technologies between formulations. Conclusions: This study provides useful information for selecting branded or generic theophylline extendedrelease dry syrups for individualized treatments.