The invention relates to an inhaler for products such as medicaments, and particularly to an inhaler for transferring to a patient a metered dose of product contained in a pressurized dispensing container. The inhaler includes a housing adapted to receive a pressurized dispensing container, a mouthpiece, duct means for connecting an outlet of the container with the mouthpiece and air inlet means for allowing air into the inhaler for when a user applies suction to the mouthpiece. The housing also comprises a mechanical break-up component located in the duct means. The component breaks up the product as it passes along the duct means, before mixing with the air flow to effect atomization of the product. The duct means includes a chamber for receiving the mechanical break-up component, the chamber having an end wall providing a barrier between the chamber and the mouthpiece to prevent the mechanical break-up component from entering the mouthpiece.