Solid state of inhalable high dose powders

Abstract

High dose inhaled powders have received increased attention for treating lung infections. These powders can be prepared using techniques such as spray drying, spray-freeze drying, crystallization, and milling. The selected preparation technique is known to influence the solid state of the powders, which in turn can potentially modulate aerosolization and aerosolization stability. This review focuses on how and to what extent the change in solid state of high dose powders can influence aerosolization. It also discusses the commonly used solid state characterization techniques and the application of potential strategies to improve the physical and chemical stability of the amorphous powders for high dose delivery.

Keywords: Aerosolization; Amorphous; Antibiotic; Chemical stability; Co-amorphous; Crystalline; Dry powder inhaler; Lung infection; Pulmonary drug delivery.