Nebulized inhalation therapy is a therapeutic method in which drugs are inhaled into the airway in the form of an aerosol with the help of an aerosol generating device to exert pharmacological effects locally in the airways.

Medical nebulizers can be divided into 3 categories: compressed, ultrasonic and mesh.
1 Air compression nebulizer The mechanism of compression nebulization is the Venturi effect, and the working principle of compression medical nebulizer is shown in Figure 1. Fluid through the restricted flow of the shrinkage hole, with the help of high-speed fluid near the low-pressure adsorption phenomenon, after the shrinkage hole in the instant the fluid pressure decreases dramatically, when the air flow through the venturi, the surrounding adsorbed liquid impact to the septum, the liquid into a fine droplet sprayed in all directions to achieve the effect of nebulization.

2 Ultrasonic nebulizer The principle is that the crystal transducer at the bottom of the nebulizer converts the electric energy into ultrasonic sound energy, generates vibration and transmits the liquid vibration in the container to the surface of the solution through the transmissive membrane at the bottom of the nebulizer tank, which causes the liquid to vibrate violently, destroying its surface tension and inertia, thus forming countless fine aerosol particles to be released.

3 The mesh type nebulizer combines the characteristics of ultrasonic nebulization, and its principle is to use ultrasonic vibration film to make it vibrate violently, and at the same time, through the extrusion technology to make the liquid pass through the tiny sieve holes of a fixed diameter, thus forming countless fine particles to be released. Conventional mesh nebulizers can only pass smaller particles and cannot meet the needs of some specific applications.