Comparison of the performance of inhalation nebulizer solution and suspension delivered with active and passive vibrating-mesh device

In the clinical use of nebulizers, the drug and device are sold separately and combined together when at use. Obviously, the matching of formulation and device is very important for the performance of nebulizer. In this study, the combinatorial influences of vibrating-mesh device and formulations were investigated. Two types of vibrating-mesh nebulizers (i.e. Aeroneb Pro nebulizer and Omron mircoAir NE-U22 nebulizer) and two types of inhalation liquids (i.e. albuterol inhalation solution and budesonide suspension) were used for comparison. The stabilities of drug (temperature, pH, osmolality, and concentration) were monitored during nebulization, and in vitro lung depositions of different drug-device combinations were measured under several breathing patterns. During nebulization, the properties of liquid in reservoir were overall stable by using vibrating-mesh nebulizer. In addition, the output rates of albuterol were higher than that of budesonide, and the nebulization time of the Aeroneb Pro nebulizer was shorter, but the total aerosol outputs of Omron nebulizer were higher. Furthermore, a "slow deep breathing"pattern will contribute to more drugs delivered into the lung. As the results of equivalence analysis between pharmacopeial testing and several breathing patterns, it was inferred that the existing pharmacopeial testing likely overestimates the dose reaching the pediatric lung. We conclude that in order to be an effective medication for patient, for a given formulation, a suitable device should be recommended based on specific drug composition and site of action. In addition, a multiple realistic breathing patterns rather than a single standardized adult breathing pattern should be considered in the evaluation of inhaled drug, which is neglected by current compendial method.