Final answer:
CS prescriptions must be rigorously maintained following DEA and state regulations, which encompass documenting, storing, and recording all transactions of controlled substances, typically for a minimum of two years, with additional specific rules for Schedule II medications.
Step-by-step explanation:
Controlled Substances (CS) prescriptions must be maintained with strict adherence to the regulations set forth by the Drug Enforcement Administration (DEA) as well as state laws. Prescribers and pharmacists are responsible for ensuring that these prescriptions are dispensed, documented, and stored securely to prevent misuse and diversion. This includes maintaining accurate records of all transactions involving controlled substances for a period specified by law, which is typically at least two years. Prescriptions for Schedule II medications, in particular, require a written prescription and cannot be refilled; a new prescription is necessary for each fill. Electronic prescriptions for controlled substances (EPCS) are subject to rigorous security standards to prevent tampering and unauthorized access.