title: Nebulizers for drug delivery to the lungs.
abstract: BACKGROUND
  Nebulizers are the oldest modern method of delivering aerosols to the lungs for the purpose of respiratory drug delivery. While use of nebulizers remains widespread in the hospital and home setting, certain newer nebulization technologies have enabled more portable use. Varied fundamental processes of droplet formation and breakup are used in modern nebulizers, and these processes impact device performance and suitability for nebulization of various formulations.
  
  
  METHODS
  This review first describes basic aspects of nebulization technologies, including jet nebulizers, various high-frequency vibration techniques, and the use of colliding liquid jets. Nebulizer use in hospital and home settings is discussed next. Complications in aerosol droplet size measurement owing to the changes in nebulized droplet diameters due to evaporation or condensation are discussed, as is nebulization during mechanical ventilation.
  
  
  CONCLUSIONS
  While the limelight may often appear to be focused on other delivery devices, such as pressurized metered dose and dry powder inhalers, the ease of formulating many drugs in water and delivering them as aqueous aerosols ensures that nebulizers will remain as a viable and relevant method of respiratory drug delivery. This is particularly true given recent improvements in nebulizer droplet production technology.
authors.affiliation: University of Alberta, Department of Mechanical Engineering , Edmonton, Alberta, T6G 2G8 , Canada warren.finlay@ualberta.ca.
authors.forename: Andrew R
authors.initials: AR
authors.lastname: Martin
authors.forename: Warren H
authors.initials: WH
authors.lastname: Finlay
mesh_terms: D000336:Aerosols; D002626:Chemistry, Pharmaceutical / Q000379:methods; D016503:Drug Delivery Systems; D006801:Humans; D008168:Lung / Q000378:metabolism*; D009330:Nebulizers and Vaporizers; D010316:Particle Size; D012121:Respiration, Artificial; D014732:Vibration
chemical_list: D000336:Aerosols
keywords: droplet formation; droplet sizing; inhalation drug delivery; jet nebulizers; nebulizers; respiratory drug delivery; vibrating membrane; vibrating mesh