1. A ventilator system of a type that delivers breathable gas to a patient at a selected system pressure and tidal volume comprising; a patient breathing tube having a first end for reception by the patient and a second end; a source of breathable gas; a conduit forming a flow path between said source of breathable gas and said second end; a source of nebulizing gas; a nebulizer housing disposed along said conduit having an upper chamber and a lower chamber and said upper chamber in combination with said flow path; said lower chamber forming a receptacle for medicine to be nebulized; said housing formed with first and second access openings; means for delivering medicine through said first access opening; means for delivering nebulizing gas from said source of nebulizing gas to said first access opening; and means for connecting alternatively, said first or second means to said first access opening.