Powdered pharmaceutical inhaler

Claim 1

An inhaler for inhalation of a powdered pharmaceutical composition from a pierceable capsule having a cylindrical side wall and hemispherical ends, said inhaler comprising a mouthpiece portion having a first end adapted for connection to a user, an opposite second end and an axis extending therebetween and a base portion having a first end, an opposite second end and an axis extending therebetween, said second end of said base portion being slidably connected over the second end of said mouthpiece portion such that the portions are in coaxial alignment and are axially slidable with respect to one another from a use position to a capsule piercing position wherein the distance between the first ends of the portions is less than the distance between the first ends of the portions in the use position, said inhaler further including means for normally biasing the portions in the use position but permitting the portions to be slid to the piercing position, said portions defining, in combination, a substantially coaxial cylindrical capsule chamber for receiving the capsule having opposite ends, an internal width in the use position, which is sized to be less than the length of the capsule and an internal length, in the use position, which is sized to be about 1.02 to 2 times the length of the capsule, said base portion defining an air inlet passage terminating in one end of said capsule chamber and the mouthpiece portion defining an air outlet passage fluidically communicating with the other end of said capsule chamber, the internal cross-section of the air inlet passage being smaller than the internal cross-section of said air outlet passage which is itself smaller than the internal width of the capsule chamber, said capsule chamber being coaxially aligned with said air inlet and air outlet passages, said mouthpiece portion defining apertures extending into said capsule chamber between said opposite ends, said apertures being located to be between the first and second ends of the base portion in the piercing position and said base portion including means therein, between said first and second ends, for aligning with said apertures and piercing, via said apertures, the cylindrical side wall of the capsule when said portions are in the capsule piercing position.