An electronically actuated droplet delivery device for delivering a low surface tension composition as an ejected stream of droplets to the pulmonary system of a subject, the device comprising: a housing; a mouthpiece positioned at an airflow exit of the device; a reservoir disposed within or in fluid communication with the housing for receiving low surface tension composition; an electronically actuated ejector mechanism in fluid communication with the reservoir and configured to generate the ejected stream of droplets; and at least one differential pressure sensor positioned within the housing, the at least one differential pressure sensor configured to activate the ejector mechanism upon sensing a pre-determined pressure change within the mouthpiece to thereby generate the ejected stream of droplets; the ejector mechanism comprising a piezoelectric actuator and an aperture plate , the aperture plate having and a plurality of openings formed through its thickness, and the piezoelectric actuator operable to oscillate the aperture plate at a frequency to thereby generate the ejected stream of droplets; wherein the ejector mechanism is configured to generate the ejected stream of droplets wherein at least about 50% of the droplets have an average ejected droplet diameter of less than about 6 microns, such that at least about 50% of the mass of the ejected stream of droplets is delivered in a respirable range to the pulmonary system of the subject during use; characterized in that the low surface composition comprises an agent that is insoluble or sparingly soluble in water, and one or more surfaces of the aperture plate are configured to provide a surface contact angle of greater than 90 degrees. a housing; a mouthpiece positioned at an airflow exit of the device; a reservoir disposed within or in fluid communication with the housing for receiving low surface tension composition; an electronically actuated ejector mechanism in fluid communication with the reservoir and configured to generate the ejected stream of droplets; and at least one differential pressure sensor positioned within the housing, the at least one differential pressure sensor configured to activate the ejector mechanism upon sensing a pre-determined pressure change within the mouthpiece to thereby generate the ejected stream of droplets; the ejector mechanism comprising a piezoelectric actuator and an aperture plate , the aperture plate having and a plurality of openings formed through its thickness, and the piezoelectric actuator operable to oscillate the aperture plate at a frequency to thereby generate the ejected stream of droplets; wherein the ejector mechanism is configured to generate the ejected stream of droplets wherein at least about 50% of the droplets have an average ejected droplet diameter of less than about 6 microns, such that at least about 50% of the mass of the ejected stream of droplets is delivered in a respirable range to the pulmonary system of the subject during use; characterized in that the low surface composition comprises an agent that is insoluble or sparingly soluble in water, and one or more surfaces of the aperture plate are configured to provide a surface contact angle of greater than 90 degrees. <EOS>