All 51 states/districts have prescription drug monitoring programs (PDMP), which helps doctors understand patients' medical history and mitigate substance abuse. If you're prescribed a controlled substance like Adderall in California, for example, your prescriber logs all activity in a database called CURES (Controlled Substance Utilization Review and Evaluation System). Any time he or she goes to refill or change your prescription, it must first be accepted by the CURES database to ensure that you haven't taken too much, or attempted to fill multiple prescriptions across different pharmacies.