Effect of Liquid Suspension on Release and Dissolution of a Theophylline Sustained-Release Dry Syrup.

Theophylline sustained-release dry syrup (TDR·DS) is reported to be effective for treating children with bronchial asthma. In the present study, we studied the release and dissolution of TDR·DS in water using THEODUR® as well as the effects of the volume and temperature of the water, and the suspension time of TDR·DS. The suspension of TDR·DS in water accelerated the release and dissolution time of theophylline. The release and dissolution times of TDR·DS at 37°C were shorter than those at 20°C. In conclusion, it is better to administer TDR·DS without suspending it in water.