title: Effect of formulation- and administration-related variables on deposition pattern of nasal spray pumps evaluated using a nasal cast.
abstract: OBJECTIVE
  To systematically evaluate the effect of formulation- and administration-related variables on nasal spray deposition using a nasal cast.
  
  
  METHODS
  Deposition pattern was assessed by uniformly coating a transparent nose model with Sar-Gel®, which changes from white to purple on contact with water. Sprays were subsequently discharged into the cast, which was then digitally photographed. Images were quantified using Adobe® Photoshop. The effects of formulation viscosity (which influences droplet size), simulated administration techniques (head orientation, spray administration angle, spray nozzle insertion depth), spray pump design and metering volume on nasal deposition pattern were investigated.
  
  
  RESULTS
  There was a significant decrease in the deposition area associated with sprays of increasing viscosity. This appeared to be mediated by an increase in droplet size and a narrowing of the spray plume. Administration techniques and nasal spray pump design also had a significant effect on the deposition pattern.
  
  
  CONCLUSIONS
  This simple color-based method provides quantitative estimates of the effects that different formulation and administration variables may have on the nasal deposition area, and provides a rational basis on which manufacturers of nasal sprays can base their patient instructions or post approval changes when it is impractical to optimize these using a clinical study.
authors.affiliation: Department of Pharmaceutical Sciences, University of Maryland, Baltimore, Baltimore, Maryland, USA. vipra.kundoor@fda.hhs.gov
authors.forename: Vipra
authors.initials: V
authors.lastname: Kundoor
authors.forename: Richard N
authors.initials: RN
authors.lastname: Dalby
mesh_terms: D000281:Administration, Intranasal; D002626:Chemistry, Pharmaceutical; D006801:Humans; D008953:Models, Anatomic; D059085:Nasal Sprays; D009330:Nebulizers and Vaporizers; D010316:Particle Size; D014018:Tissue Distribution; D014783:Viscosity
chemical_list: D059085:Nasal Sprays