According to an aspect of the invention, implantable or insertable medical devices are provided which contain the following: (a) one or more porous regions comprising pores and (b) one or more therapeutic agents which are (i) contained within the porous region, (ii) disposed beneath the porous region, or (iii) both. Moreover, the porous regions are capable of undergoing a change in configuration, such that the pores undergo a change in configuration, upon subjecting the porous regions to activating stimuli.