Effect of drug targeting nebulization on lung deposition: a randomized crossover scintigraphic comparison between central and peripheral delivery.

BACKGROUND Recent technological advances in nebulization permit researchers to target specific parts of the lungs by modifying delivery method. The aim of this study was to compare the central and peripheral targeted modalities of administration. METHODS Lung and regional deposition of inhaled technetium-99m diethylene triamine penta-acetic was measured by scintigraphy after peripheral and central targeted modalities of administration with an Akita device in 6 healthy subjects. RESULTS Drug targeting nebulization delivered a large amount of drug into the peripheral part of the lung independent of the modality (outer-to-inner deposition ratio of 1.24 ± 0.21 vs. 1.22 ± 0.14 for central and peripheral modalities, respectively), but there was no difference in lung deposition (whole-body deposition, 83.3 ± 6.5% vs. 82.8 ± 7.3%, P = .86) or regional deposition (P = .77) between both modalities. The extrathoracic deposition was < 20% of the whole-body deposition, without a difference between modalities (P = .86). CONCLUSIONS This study shows for the first time that choosing 2 different specific drug targeting nebulization modes does not influence the amount of drug delivered into the lung in healthy male subjects. Moreover, the modes do not modify the site of deposition under the conditions of our study.