An inhaler device for delivery of at least one active substance to an inhaling user, the inhaler device comprising:a first conduit for conducting airflow to an opening from which the user inhales；a valve positioned and configured to affect flow of ambient air into the first conduit；a controller configured to control release of the at least one active substance to be carried by the airflow to the inhaling user, the controller further configured to control the valve to generate a pattern of airflow modulations, the pattern including:(a) delivering the active substance via the airflow followed by substantially reducing a total rate of airflow to the user for an intermediate period, and then(b) increasing the airflow to a rate or volume sufficient to decrease a resistance sensed by the inhaling user.
