An apparatus and method for providing a nebula or aerosol to a patient is described. In one aspect, the nebulizer is composed of a minimum number of parts to reduce complexity for automated or human assembly. The nebulizer may include an inhalation valve, exhalation valve and biasing member integrated into a single diaphragm structure that may be connected with an actuator and inserted into a housing for controlling nebulization of a medicine to a patient in response to the patient's breathing or in a continuous nebulization mode.