Aerosol therapy consists of administering drugs directly to the respiratory tract to treat a number of pathologies of the nose, throat, bronchi and lungs. The aerosol is a suspension of solid particles and/or liquid droplets which, passing through the nose and the mouth, enter the respiratory tract and go deep into the larynx, the pharynx, the trachea and reach the lungs where they enter into contact with the bronchial mucosa and with the alveoli.
The settling of such particles depends on their dimensions. The ideal diameter for these droplets to reach the whole respiratory tract ranges from 0.8-2 to 5-8 microns: particles with a large diameter are absorbed by the upper respiratory tract, while the smaller ones reach the bronchioles and the alveoli.
