[Theophylline-retard preparations: relation between drug liberation in vitro and their behavior in the human body].
Using theophylline retard preparations, the course of drug concentration in serum can be read from the speed of drug liberation estimated in vitro. For preparations with a strong retard effect we have to calculate a diminished bioavailability. The management of therapy in the therapeutical range and without side effects is possible with preparations with nearly complete bioavailability, nevertheless theophylline remains a problem drug. Firstly, the interindividual deviations are excessive great, with the usual standard dose caused by the different body mass and by the different biotransformation. Secondly, the "Food induced dose dumping" is appearing if taking drug and food is unsuitably coupled. Summarizing the present results, several steps for further optimization of therapy with theophylline retard preparations are proposed.