Lockout device for controlled release of drug from patient-activated dispenser

A method of controlling access to a drug in an aerosol drug delivery device by an electronic lock and key means is disclosed. Access is limited to the intended user by providing the intended user with a uniquely coded, machine readable key means that matches the unique code of the lock means. Contacting matching lock and key means signals a controlling means to allow use of the device. Specifically, the method is applied to a method of pain control provided by the intrapulmonary delivery of a pharmaceutically active pain relief formulation. The formulation is automatically released form a hand held, self-contained, portable device (1) comprised of a means to automatically release a measured amount of drug into the inspiratory flow path (11) of a patient in response to information obtained from a means (21) for measuring, and separately determining inspiratory flow rate and inspiratory volume of a patient.