The invention provides a device (10) for conserving and extemporaneously preparing at least one active principle prior to administration, the device comprising: a body (12) that is constituted by at least one compartment for containing at least one volume of pharmaceutical solvent (22) that is less than 5 mL a head (14) constituted by at least one compartment for containing at least one active principle (24), in particular a very small dose, and, in its top portion, by at least one dose-taking chamber (32) provided with a filter (40), the head (14) being capable of taking up a first position P1 for conservation, in which said head (14) is in its distal position relative to the body (12), and a second position P2 for preparation, in which said head (14) is in its proximal position relative to the body (12) at least one wall (16) separating the body (12) and the head (14) and rupture means (18) for rupturing said wall (16) so that the active principle (24) enters into contact with the solvent (22) and dissolves therein. The invention also seeks to use the device for conserving and extemporaneously preparing at least one active principle with a view to administering it.
