Unit dose cartridge and dry powder inhaler

Abstract

A dry powder inhaler having improved aerodynamic properties for diluting, dispersing, and metering drug particles for increasing the efficiency of pulmonary drug delivery to a patient is described. The inhaler comprises, in general, a housing having an air intake, an airflow-control/check-valve, a mixing section and a mouthpiece. A cartridge loaded with a single dose of medicament can be installed in the mixing section.

We claim: 
     
         1 . An inhaler comprising:
 a mixing cavity adapted to mount a medicament-containing cartridge, wherein airflow exiting the medicament-containing cartridge during an inhalation is configured to meet a shearing flow.   
     
     
         2 . The inhaler of  claim 1 , wherein the medicament-containing cartridge includes a drug powder. 
     
     
         3 . The inhaler of  claim 1 , wherein the shearing flow is from airflow that does not flow through the medicament-containing cartridge. 
     
     
         4 . The inhaler of  claim 1 , wherein the shearing flow is from cartridge bypass airflow. 
     
     
         5 . The inhaler of  claim 1 , further comprising a mouthpiece. 
     
     
         6 . The inhaler of  claim 5 , wherein the mouthpiece includes a transport conduit with an expansion wall having a divergence angle configured to create a horizontal discharge path. 
     
     
         7 . The inhaler of  claim 6 , wherein the horizontal discharge path has a 3:1 aspect ratio. 
     
     
         8 . The inhaler of  claim 6 , wherein the divergence angle is about 3 degrees. 
     
     
         9 . The inhaler of  claim 5 , wherein the mouthpiece is configured to diverge an air stream of particles when the inhaler is in use. 
     
     
         10 . The inhaler of  claim 5 , wherein the mouthpiece is configured to converge an air stream of particles when the inhaler is in use. 
     
     
         11 . The inhaler of  claim 5 , wherein the mouthpiece is configured to converge an air stream of particles to aim the particles when the inhaler is in use. 
     
     
         12 . The inhaler of  claim 5 , wherein the mouthpiece is connected to the mixing cavity by a joint. 
     
     
         13 . An inhaler comprising:
 an air pathway configured to generate a shearing flow, wherein the shearing flow is directed to meet airflow exiting a medicament-containing cartridge during an inhalation.   
     
     
         14 . The inhaler of  claim 13 , wherein the medicament-containing cartridge includes a drug powder. 
     
     
         15 . The inhaler of  claim 13 , wherein the shearing flow is from airflow that does not flow through the medicament-containing cartridge. 
     
     
         16 . The inhaler of  claim 13 , wherein the shearing flow is from cartridge bypass airflow. 
     
     
         17 . The inhaler of  claim 13 , further comprising a mouthpiece connected to a mixing section by a joint. 
     
     
         18 . The inhaler of  claim 17 , wherein the mouthpiece is configured to diverge an air stream of particles when the inhaler is in use. 
     
     
         19 . The inhaler of  claim 17 , wherein the mouthpiece is configured to converge an air stream of particles when the inhaler is in use. 
     
     
         20 . The inhaler of  claim 13 , wherein the inhaler is a dry powder inhaler.