Final answer:
DEA Form 222s for controlled substances must be kept for two years to comply with regulatory requirements, ensuring proper inventory and transaction records.
Step-by-step explanation:
Controlled substances executed DEA Form 222s must be maintained for two years. The United States Drug Enforcement Administration (DEA) requires that records associated with the schedules I and II controlled substances, which are executed using DEA Form 222, be kept for a minimum of two years for compliance with regulatory requirements. This is crucial for ensuring that pharmacies, hospitals, and other entities that handle these highly regulated substances have a proper account of their inventories and transactions to prevent diversion and ensure the integrity of the distribution chain.