Abstract: A drug delivery apparatus of the type which releases a drug in aerosolized form into the inhaled airstream of a person, programmed to release the drug in a pulse which ends a pre-set time before the person is expected to stop inhaling. In doing so, a minimum residence time within the lungs is created, and drug treatment time can be reduced. A corresponding method of controlling a drug delivery apparatus comprises the step of controlling the apparatus to release the drug in aerosolized form into the inhaled airstream of a person in a pulse which ends a pre-set time before the person is expected to stop inhaling.