A device useful for oral
drug delivery device consisting of: (a) a
capsule, tablet or
pill designed to disperse in the
gastrointestinal system; (b) an RFID tag positioned in the
capsule, tablet or
pill, the RFID tag comprising an antenna; (c) an object selected from the group consisting of a
magnet, a ferromagnetic object, a ferrite object and an
electromagnetic shielding object positioned within, over or adjacent the antenna of the RFID tag to alter the antenna characteristics of the RFID tag so that if the RFID tag is interrogated before the
capsule, tablet or
pill disperses in the
gastrointestinal system, the response of the RFID tag is sufficiently altered or attenuated to determine that the capsule, tablet or pill has not dispersed in the
gastrointestinal system and so that if the RFID tag is interrogated after the capsule, tablet or pill has dispersed in the gastrointestinal
system, the object separates from the RFID tag so that the response of the RFID tag is sufficiently detectable to determine that the capsule, tablet or pill has dispersed in the gastrointestinal
system. Alternatively, a switch can be used to
signal ingestion of the device, and change the response of the device. In another embodiment, the instant invention is a device useful for oral
drug delivery, consisting of: (a) a capsule, tablet or pill designed to disperse in the gastrointestinal
system; (b) a first non-anti-collision RFID tag positioned in the capsule; (c) a second non-anti-collision RFID tag positioned in the capsule, so that if the RFID tags are interrogated by an RFID reader before the capsule, tablet or pill disperses in the gastrointestinal system, the response of the RFID tags collide and so that after the dispersible material of the capsule has dispersed in the gastrointestinal system thereby allowing the first and second non-anti-collision tags to separate from each other, then the response of the RFID tags is sufficiently different from each other to determine that the capsule has dispersed in the gastrointestinal system