Method for determining anesthesia dosage includes following steps. First Interventional Agent (“FIA”) is administered to Patient at a first rate to achieve First Predetermined Plane of Anesthesia (“FPPA”). Brain waves of Patient are analyzed to formulate First Set of Data (“FSD”) corresponding to a self-norm during administration of FIA. First transfer function corresponding to patient biochemical reactions to FIA is computed from FSD. Rate of administration of FIA to Patient is altered by a selected amount after achievement of FPPA for first time required for Patient to deviate from FPPA by predetermined degree. An altered amount of FIA required to cause the predetermined deviation is determined as difference between amount of FIA that would have been delivered to Patient during first time at the first rate and an amount delivered to Patient during the first time at the altered rate. Patient is administered the altered amount of FIA.