title: Pulmonary dispersion formulations: the impact of dispersed powder properties on pressurized metered dose inhaler stability.
abstract: Suspension-type metered dose inhaler formulations characteristically have a high degree of dispersion instability. This may occur as the result of any of a large number of formulation issues including phase separation, particle growth, agglomeration/flocculation, moisture ingress, and particle interactions with both the canister material and other particles. Many of these undesirable instabilities may arise as a result of the physical and chemical properties of the dispersed powder in the liquid propellant system. As such, this review provides a detailed understanding of the characteristics of the dispersed phase in the liquid propellant system necessary to ensure stability of the final formulation.
authors.affiliation: The University of Texas, College of Pharmacy, Division of Pharmaceutics, Austin, TX 78712, USA.
authors.forename: Kevin P
authors.initials: KP
authors.lastname: O'Donnell
authors.forename: Robert O
authors.initials: RO
authors.lastname: Williams
mesh_terms: D000280:Administration, Inhalation; D016503:Drug Delivery Systems; D004355:Drug Stability; D058995:Dry Powder Inhalers / Q000295:instrumentation*; D006801:Humans; D008168:Lung / Q000187:drug effects*; D036501:Metered Dose Inhalers; D010316:Particle Size; D011208:Powders
chemical_list: D011208:Powders