Abstract: A decision support system and method for optimizing medication dosages includes comprehensive patient databases correlating medications and exposure values across data models having pharmacokinetic and pharmacodynamic dimensions. The system determines distinctions between expected and detected medications and exposure values for a patient, and further distinguishes between non-compliant patients from compliant patients having high metabolizing characteristics with respect to certain expected but undetected medications. The system links to and reconciles the patient medical record accordingly. Graphical user interfaces display recommended dosages and projected exposure ranges for the expected and detected medications. In an embodiment, the interface presents certain alternative treatment options determined as being available with respect to the expected but undetected medications.