- Author(s):
- Organization(s):
Applied Particle Principles, LLC Jolyon Mitchell Inhaler Consulting Services, Inc.
In this article we seek to define, as well as to elucidate the origin of, the terminology associated with understanding and reporting the data obtained when testing an orally inhaled product with a cascade impactor. In doing so, we aim to provide a clear and accessible resource both for seasoned participants and newcomers to the medical aerosol laboratory.
Use of the multi-stage cascade impactor (CI) is the only technique approved by regulatory agencies for characterizing the mass-weighted aerodynamic particle size distribution (APSD) of particles emitted from all types of orally inhaled products (OIPs). However, despite the regulatory and industrial consensus on the need for this method, there is little definition in regulatory guidance documents or pharmacopeial handbooks about what constitutes “characterizing” these inhaler-generated particles.