Computer-controlled drug release from small-sized dosage forms

For the construction of dosage forms where the release of drugs can be varied, under computer control, according to some chosen parameter such as the therapeutic effect, new structural principles are required. Drug release systems were developed in which the controlling elements required for a complete regulating circuit such as sensor, microprocessor and application form are separated from each other. The components are connected by a remote control. The release mechanism is regulated via a magnetic or high frequency field. Release is directed by a computer program. A complete computerized system for a feedback-controlled drug release, including monitoring and control devices requires a considerable outlay on apparatus. In order to miniaturize a feedback-controlled delivery system, dosage forms were developed which are controlled by microorganisms. The activity of the biosystem is substrate-dependent Drugs or physiologically relevant substances may enhance or reduce the activity of the biosystem. An ideal biosystem acts as the sensor, the data processing unit and the energy source for a feedback-controlled drug delivery device. Using a biosystem, glucose-controlled insulin delivery systems were developed. (C) 1997 Elsevier Science Ireland Ltd.