Methods and apparatus for delivering aerosolized medication

Abstract

A pulmonary drug delivery device having one or more vortexing elements which impart beneficial flow characteristics to an inspiratory air flow carrying a medicament into the patient's lungs.

We claim: 
     
         1 . An aerosol flow control apparatus for use in a pressurized metered dose inhaler, said apparatus comprising:
 (a) a housing defining a conduit, said conduit having an open end that provides a mouthpiece, a substantially closed end, and a vortexing back plate positioned remotely from the open end and defining the substantially closed end; said vortexing back plate comprising a first set of vortexing air inlets in fluid communication with ambient air outside the conduit;   wherein said vortexing back plate is disposed in the conduit such that the first set of vortexing air inlets opens into a direction towards the mouthpiece; and   wherein said first set of vortexing air inlets is angled so as to impart a vortexing motion to the ambient air drawn into the conduit through the first set of vortexing air inlets; and   (b) a pressurized canister comprising a medicament, said pressurized canister arranged within the housing to direct a bolus of the medicament into the conduit.   
     
     
         2 . The aerosol flow apparatus of  claim 1 , further comprising a second set of vortexing air inlets disposed about the periphery of the vortexing back plate. 
     
     
         3 . The aerosol flow apparatus of  claim 1  or  2 , wherein the vortexing air inlets comprise inwardly directed vanes which are oriented at an angle. 
     
     
         4 . The aerosol flow apparatus of  claim 2 , wherein the second set of vortexing air inlets are triangular in shape so as to impart a further vortexing motion to the air drawn into the conduit through the first set of vortexing air inlets. 
     
     
         5 . The aerosol flow apparatus of  claim 1 , wherein the votexing back plate is located behind the position at which the medicament bolus is introduced into an inspiratory air flow. 
     
     
         6 . The aerosol flow apparatus of  claim 1  or  2 , wherein the vortexing air inlets impart a tangential velocity to an inspiratory air flow and create a helical swirl pattern to the inspiratory air flow and to the medicament bolus, and wherein the medicament bolus flow rate is slowed and approximately matches the inspiratory air flow rate. 
     
     
         7 . The aerosol flow apparatus of  claim 1 , wherein the mass median aerodynamic diameter of the medicament bolus is less than about 10 microns. 
     
     
         8 . The aerosol flow apparatus of  claim 1 , wherein the mass median aerodynamic diameter of the medicament bolus is from about 1 micron to about 5 microns. 
     
     
         9 . The aerosol flow apparatus of  claim 1 , wherein the medicament bolus has a velocity of less than about 300 centimeters per second. 
     
     
         10 . The aerosol flow apparatus of  claim 1 , wherein the medicament bolus has a velocity of less than about 150 centimeters per second.