A disposable device for atomising a liquid is provided, comprising a housing 12 having a reservoir of liquid 16 connected to a nebulising nozzle 18 and a sealed space 13 containing a cylinder of pressurised gas 14. The housing also has a moveable barrier 20 which separates the reservoir from the sealed space. In operation, the device allows the pressurised gas to escape from the cylinder into the sealed space, and act on the moveable barrier, to force liquid in the reservoir to pass through the nozzle and be emitted as an aerosol. The moveable barrier 20 may be a piston or deformable membrane and may have a piercing element 26 for piercing the cylinder 14.
