A monitor into which a standard medication blister package 209 may be placed, the tray comprising a plurality of cells containing medication, the monitor comprising sensors 602 that detect which cells in the medication tray have been opened, and a means of transmitting this information wirelessly to remote servers, via an intermediate communication gateway. The monitor also has a display screen upon which messages relating to the use of the medication are displayed. The means of detecting opened cells include infrared proximity sensors, capacitive sensors, inductive sensors, mechanical switches and paired optical emitters and detectors. The apparatus allows medical professionals to check if medication is being taken as prescribed.
