Described is a method for the delivery of a therapeutic agent to a mammal, particularly a human person, comprising (i) the administration of ultrasound particles that undergo a physical change when subjected to ultrasound； (ii) the administration of the therapeutic agent in an ultrasound dosage form allowing release of the therapeutic agent to be affected by the application of ultrasound, (iii) the application of ultrasound so as to affect a physical change in at least some of the ultrasound particles, and (iv) the application of ultrasound so as to stimulate release of the therapeutic agent. According to the invention the ultrasound particles are subjected to detection of their acoustic responses via echoes and/or emissions. The information thus obtained is processed and the processed information is used to adapt or adjust the ultrasound-mediated delivery of the therapeutic agent. This can be carried out using a single set of particles (that serve both as ultrasound imaging tracers and as drug delivery vehicles) or by applying separate sets of particles.
