A drug delivery adapter is configured to facilitate the delivery of one or more medicaments to a subject being ventilated by a circuit (not shown). The circuit may be a ventilator circuit, or the like, configured to convey a pressurized flow of breathable gas to the airway of the subject. The ventilator circuit may form a flow path between a pressure generator and the airway of the subject to deliver a pressurized flow of breathable gas from the pressure generator to the airway of the subject.