Attributes describing the quality and testing of inhalation drug products are contained within international pharmacopoeias, regulatory guidance from the international Health authorities, ICH guidelines and ISO standards. There are currently wide differences in the use of these attributes between international regulatory guidance, usage in literature and by companies. Different terms for the same quality attributes were collected from the various sources to make the broad variety visible. The terms were grouped according to their use and listed together with their source in tabular lists. This list was then distributed to all European Pharmaceutical Aerosol Group (EPAG) member companies with the request for them to indicate their most commonly used terms. This survey presents the most commonly used terms for quality attributes by two thirds of the EPAG member companies and highlights the need for harmonization in regulatory guidance and communication. Such harmonization over all regions of the world would be a valuable goal to achieve and would ease the compilation of documentation for international submissions or company internal documents. As a starting point for international attempts to achieve this goal, this survey is published with the target to encourage individuals and organizations that are responsible for the determination of binding terms for inhalation products in pharmacopoeias and regulatory guidance to aim for consolidation and harmonization of the terminology in all regions. Since the current difference in terminology creates a burden for internationally operating companies, EPAG is more than willing to support all attempts that aim for harmonization.
