Powder inhaler devices

Carter, P. A., Rowley, G., Fletcher, E. I, and Sylianopoulos, V. (1998), Measurement of electrostatic charge decay in pharmaceutical powdersand polymer materials used in dry powder inhaler devices, Drug Dev. Ind. Pharm., 24,1083-1088. 

B. J. Lipworth, and D. J. Clark, Lung delivery of salbutamol given by breath activated pressurized aerosol and dry powder inhaler devices, Pulm. Pharmacol. Ther. 70 211 (1997). 

Early dry powder inhaler devices were all unit-dose systems and depended on loading and triggering procedures. The Spinhaler and Rotahaler are two early examples of DPI technology. Both utilize premetered doses packed into hard gelatin capsules although different mechanisms of powder delivery are employed ... 

I) powder production and formulation and (II) powder inhaler devices. 

Recent inventions of the powder inhaler device are aimed at improving the inhaler s dispersion efficiency and reducing the resistance of the device as well as decoupling powder dispersion from the patient s inspiratory effort in order to deliver accurate and flexible dosages for different patient s needs. 

Powder inhalation devices are currently proving very popular, in spite of the fact that patients generally prefer metered dose aerosols. However, this preference is counterbalanced by the fact that compliance is much more difficult to achieve with aerosols. There is also a third category where the pack and the device are totally independent, e.g. a unit dose of nebuliser solution which is subsequently transferred to a pressurised or an ultrasonic nebuliser unit for delivery to the patient. 

Nasal spray Inhalation spray Inhalation solutions and suspensions Metered dose inhaler MDI Dry powder inhaler DPI, device metered Dry powder inhaler DPI, pre-metered Not included Non-pressurized metered dose nasal spray Nasal single use sprays Non-pressurized metered dose inhaler Product for nebuhzation (single and multiple use) Pressurized metered dose nasal sprays Pressurized metered dose inhaler Dry Powder Inhaler, device metered Nasal powders, device metered Dry Powder Inhaler, pre-metered Nasal drops (single and multiple use)... 

Daniels GF, Ashurst 1C, Malley TR, Walker S, Noble R, Gillet B. Simulated patient in-use testing at extreme environmental conditions of a dry powder inhaler device containing a combination of salmeterol and fluticasone propionate (abstr). Eur J Respir 1999 14 (suppl 30) 2284. 

Kesten S, Elias M, Cartier A, Chapman KR. Patient handling of a multidose dry powder inhalation device for albuterol. Chest 1994 105 1077-1081. 

Engel T, Scharling B, Skovsted B, Heinig JH. Effects, side effects and plasma concentrations of terbutahne in adult asthmatics after inhaling from a dry powder inhaler device at different inhalation flows and volumes. Br J Clin Pharmacol 1992 33 439 44. 

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