A holder (1) for storing a blister package between times of use, has a flat panel (2) in which re embedded an array of light sensors (3). Coplanar channels (8) bordering the panel (8) enable a blister package to be inserted into the channels (8) until it occupies a predetermined position at which one marginal edge engages with, and closes, a pair of switches (12). A pair of easily-disconnectable straps (13) hold the package in the predetermined position between times of use. When at the predetermined position, the regions of a friable backing strip forming part of the package lies opposite respective sensors (3). Each sensor incorporates a light transmitter which, when energized, directs a beam of light against the region of the foil closing the associated blister. The reflectivity characteristic of the region is greater when the foil is intact than when the foil is ruptured by the ejection through it of the contents of the associated blister. This characteristic of the foil can be monitored and used to determine when the associated blister has been opened. Electrical circuitry is used to record the time at which opening occurred and this can be compared with a record of the times at which a blisters should have been opened in order to comply with the requirements of a medical prescription.La présente invention concerne un support (1) permettant de stocker une plaquette entre des temps dutilisation, et qui comporte un panneau plat (2) dans lequel est incorporé un réseau de capteurs de lumière (3). Des canaux coplanaires (8) bordant le panneau (2) permettent quune plaquette soit insérée dans les canaux (8) jusquà occuper une position prédéterminée au niveau de laquelle un bord marginal vient en contact avec une paire de commutateurs (12) et ferme ceux-ci. Une paire de bandes (13) pouvant être facilement disjointes maintient la plaquette dans la position prédéterminée entre les temps dutilisation. Lorsque la plaquette se trouve dans ladite position prédéterminée, les
