The invention provides systems and methods for providing integrated paced breathing and inhalation therapy to a patient. Paced breathing includes alternately providing a high and a low airway pressure to a respiratory system of the patient using a breathing circuit, wherein the high airway pressure coincides with inhalation by the patient and the low airway pressure coincides with exhalation by the patient. A therapeutic substance is delivered to the respiratory system of the patient during the provision of high airway pressure to the respiratory system of the patient, wherein delivery of the compound to the respiratory system of the patient is discontinued during provision of low airway pressure to the respiratory system of the patient.