METERED DOSE INHALER

A metered dose inhaler (1) for dispensing aerosol doses comprises an actuator housing (2) in which an aerosol container (6) with an activation valve (7) is inserted. The container (6) is configured to move in a longitudinal direction (A) from a rest position to an activation position in which the valve (7) is depressed against a bottom portion (9) of the actuator housing (2) such that an aerosol dose is released. A triggering unit (11) comprises at least a first trigger member (12a), which is configured to interact with the container (6) moving in the longitudinal direction (A). The first trigger member (12a) triggers a first switch (16a) of an electronic unit (14) when the container (6) reaches a first longitudinal position during its movement from the rest position to the activation position. A counting circuit (17) is configured to receive a signal from the first switch (16a) indicating at least a first time when the first switch (16a) is triggered by the first trigger member (12a). The electronic unit (14) is detachable from the actuator housing (2) independently from the triggering unit (11). The electronic unit (14) is configured to be reusable in combination with another metered dose inhaler (1).