Pulsatile drug delivery systems

The ability to deliver therapeutic agents to a patient in a pulsatile or staggered release profile has been a major goal in drug delivery research recently. This review will cover methods that have been developed to control drug delivery profile with different polymeric systems. Externally and internally controlled systems will be considered, including a range of technologies like preprogrammed systems as well as systems that are sensitive to modulated enzymatic or hydrolytic degradation, pH, magnetic fields, ultrasounds, electric fields, temperature, light and mechanical stimulation. These systems have the potential to improve the quality of life for patients undergoing therapy with a variable dosing regime.