The invention refers to a spray device and a method for cleaning and moistening the nasal cavity and the paranasal sinuses, said device being characterized in that it is adapted to the connector portion of a syringe. The device has two end portions, one acting as a syringe connector and the other allowing the nasal cavity to be completely and comfortably sealed due to its ergonomical form. The device is characterized in that it has an end to end perforation, which is useful as a conduct for flowing the saline solution to be introduced into the nasal cavity so as to be cleaned and moistened, also acting as a dampener of the injected saline solution flow, thus turning the nasal cleaning process into a more agreeable, easy and effective process. In addition, the invention also includes a method for cleaning and moistening the nose, which is characterized in that it uses saline solutions formed by sodium chloride and sodium bicarbonate in equal ratios, mixed with natural herbal extracts. Said herbal extracts increase the benefits obtained from cleaning the nasal cavity, which forms an essential part of the treatment of upper airway infections such as rhinitis, sinusitis, cold and chronic nasal obstruction, amongst others. 1.Esta invención hace referencia a un dispositivo dispersor y a un método de limpieza y humectación de la cavidad nasal y senos paranasales, dicho dispositivo se caracteriza por ser adaptable al extremo conector de una jeringa de cualquier medida. Este dispositivo posee dos extremos, uno hace la función de conector a la jeringa y el otro permite un sello completo y confortable de la fosa nasal debido a su forma ergonómica. Dicho dispositivo se caracteriza por tener una perforación de extremo a extremo, que sirve como conducto de paso para las soluciones salinas que se desean introducir en la cavidad nasal para su limpieza y humectación, el cual tiene además la función de amortiguar la presión del flujo inyectado de soluciones salinas haciendo más agrad
