Abstract: The present apparatus includes a metered dose inhaler (MDI) portion housed with a heat and moisture exchanger (HME) portion. The MDI portion and the HME portion share an inlet. The MDI portion and the HME portion share an outlet. The MDI portion and the HME portion are in parallel to each other and are immediately lateral of one another. The present MDI/HME apparatus includes a valve to direct fluid flow to or away from the HME portion and to or away from the MDI portion. The present MDI/HME apparatus includes a valve arm to communicate to the caregiver whether fluid is passing through the MDI portion or the HME portion and to structurally close off an MDI port when the valve is open relative to the HME portion. The valve is structured such that fluid flow to the patient is never obstructed.