A system and method for controlling the administration of medication to a patient utilizes adaptive feedback to achieve and maintain a target effect in said patient. A sensor package having one or more sensors is used to sense an attribute of the patient and to provide a parameter indicating the attribute being sensed. A medication delivery controller accepts one or more parameters from the sensor package and uses these parameters to determine the effect of a medication on a patient and the concentration level of medication that will achieve a desired effect. The medication delivery controller controls the medication delivery unit to deliver the medication at a rate determined to achieve said target concentration level of said medication in said patient. If the patients response to a given medication changes as a result of external stimuli, the medication delivery controller can detect this change and determine a new concentration level of medication which will achieve the desired effect. The medication delivery controller can steer the medication delivery unit to administer an amount of medication to reach this new concentration level.
