4.1 Introduction Manufacturing of suspension-type metered-dose inhaler (MDI) and dry powder inhaler (DPI) products for pulmonary drug administration requires powders with desirable characteristics, including particle size, shape, density, crystallinity, surface…

6.1 Introduction Impactors are the official instruments for determining the particle size distribution of aerosols generated from medical inhalers and nebulizers. They directly measure the aerodynamic particle size, which affects…

2.1 Introduction Pharmacologically active substances have been administered to humans for thousands of years, but delivery via the lung is a relatively recent development. Commercialization of inhaled respiratory medicines was…

3.1 Introduction Chapter 2 highlighted the different approaches and commercial devices used to deliver medicines to the respiratory tract. For the routine treatment of nonsevere asthma, the two most commonly…

8.1 Introduction Unlike the minimal trial-and-error approach, a systematic drug-product development process (also known as “quality by design,” QbD) includes prior knowledge, the results of experimental designs, quality risk management,…

9.1 Introduction The finished-product specifications define the quality that every product must exhibit in order to fulfill the requirements of safety and efficacy. These critical quality aspects are identified and…

5.1 Introduction 5.1.1 The Complexities and Challenges of Aerosol Performance Arguably, aerosol drug-delivery systems (inhalers) represent the most complex of medicinal products. Understanding the scientific principles and mechanisms that determine…