An aerosolization device comprises a housing having a mouthpiece, and a flow path arrangement in fluid communication with the mouthpiece. The flow path arrangement has a flow regulating valve and a threshold valve, where the threshold valve is configured to open at a first vacuum level and to close at a second vacuum level that is less than the first vacuum level. The housing includes a region that is adapted to hold a powder in fluid communication with the flow path arrangement so that air drawn through the mouthpiece opens the threshold valve once the first vacuum level is exceeded and remains open until the vacuum falls below the second vacuum level. The flow rate of the air drawn through the mouthpiece is regulated by the flow regulating valve to remain within a certain range while the threshold valve remains open.