For how long must an inventory record of controlled substances be maintained?

The correct answer reflects the requirement set by regulatory agencies regarding the maintenance of inventory records for controlled substances. Under federal law, specifically the Drug Enforcement Administration (DEA) regulations, practitioners and pharmacies are required to keep these records for at least two years. This duration allows for sufficient oversight and potential audits to ensure compliance with laws governing the distribution and use of controlled substances.

Maintaining records for two years provides accountability and helps prevent misuse or diversion of these substances while ensuring that veterinary practices can effectively manage their inventories. This period is a balance between regulatory efficiency and the practical needs of veterinary practices in maintaining oversight of controlled substances.

The other durations presented do not align with these regulatory requirements; for example, one year may not provide adequate time for auditing purposes, while three and five years extend beyond what is mandated, potentially leading to unnecessary additional record-keeping burdens on veterinary practices.