The invention comprises a medicinal inhaler spacer or actuator comprising a chamber having a proximal end closed by a proximal plate, a tangentially aligned inlet on the proximal end of the chamber, a tapered distal end, and an outlet extending through the proximal plate into and communicating with the chamber. Spacers of the present invention may be used to increase the respirable fraction of a medicinal aerosol inhaler. The invention also comprises medicinal aerosol inhalers and methods of delivering drug to the lung of a mammal employing these spacers.