Abstract: The invention relates to a spray-diffuser for the atomization of liquids or solid substances, such as medicaments, with the help for the flow of compressed air, particularly for inhalation purposes. The spray-diffuser comprises a spray-diffuser nozzle (3) located in an atomizing chamber (10), which nozzle is connected to a compressed air channel (2) and comprises a suction device for sucking up the medicament, wherein the compressed air channel adjacent the nozzle has a release opening (15) for escape of the compressed air, which opening is settable to a non-operation position, and which can for example be closed during inhalation of the patient and opened during exhalation of the patient. In known spray-diffusers, diverted air is guided through the release opening with a development of a hissing noise and a danger of harm to the staff. In order to avoid this disadvantage, in the spray-diffuser according to the invention the release opening leads into the atomizing chamber.