A nebulizer includes a body, an air channel section and medication reservoir. An air line extends through the air channel section. A venturi nozzle is configured to form at its end a low pressure mixing chamber. A primary suction line extends from the medication reservoir to the low pressure mixing chamber through which medication is drawn upward into the low pressure mixing chamber and mixed with air from the venturi nozzle and nebulized for discharge through a nebulizer outlet. The venturi nozzle, low pressure mixing chamber and air channel section are configured such that at standard temperature and pressure (STP) a differential pressure results in no medication that is drawn upward through the primary suction line for nebulization and discharged the through the nebulizer outlet until a negative inspiratory pressure is created from inhalation by a user.