The method and system according to preferred embodiments of the present invention allows optimizing the dispensing of aerosol medicaments by "pulsing" a total dose volume as a series of shorter, low volume bursts. Aerosol performance when metering at a low volume e.g. <；10µL is enhanced by an increase in the fine particle fraction, particularly when pulsing a dose to achieve a high total dose volume. By utilising a solenoid valve, we can deliver a medicament in a single low volume pulse； or in multiple low volume pulses. Performance can be tailored to obtain a preferred fine particle dose and fraction. By manipulating the solenoid valve timings, a single formulation with a concentration X may be used to provide a range of doses e.g. 5µg； 100µg； 200µg； 400µg. We have explored the minimum interval between pulses to achieve separate "non-interacting" plumes which allow keeping total inhalation time comparable to a conventional single dose MDI actuation. Furthermore, the flexibility of this system allows exploring multiple valve systems with separate control- to synchronise alternate dosing from two or more separate formulations whilst achieving improved, but individual, aerosol characteristics.
