The present invention relates to an inhalation device for use with an inhaler (5) comprising a dispersion chamber (18) for fluid communication with the inhaler (5) and a suction chamber (19) in fluid communication with the dispersion chamber (18). The suction chamber (19) is constructed to enable the internal volume of the suction chamber (19) to be increased during use thereby producing a negative pressure in the dispersion chamber (18). In this way, the substance to be inhaled can be drawn from the inhaler into the dispersion chamber (18) for subsequent inhalation.
