How long must a perpetual inventory for schedule II controlled substances be maintained?

The correct duration for maintaining a perpetual inventory for Schedule II controlled substances is two years. This requirement aligns with federal regulations and many state laws which mandate that records related to controlled substances, including inventory records, must be retained for a minimum of two years from the date of the last entry.

This regulation ensures that there is a proper framework for tracking controlled substances and helps in monitoring for any discrepancies, potential misuse, or diversion. The two-year retention period allows regulatory agencies to conduct audits and pharmacy inspections effectively, ensuring compliance with laws governing controlled substances.

Maintaining records indefinitely would be impractical and unnecessary, as it could lead to storage and organizational challenges. Conversely, maintaining records for just one year falls short of the regulatory requirements aimed at comprehensive oversight of controlled substance management. Therefore, the appropriate answer reflects adherence to the established guidelines for record retention.