Final answer:
A controlled substance inventory is typically required to be conducted annually by the DEA under federal law, with the possibility of more frequent inventories depending on state and classification of the substance.
Step-by-step explanation:
According to the Drug Enforcement Administration (DEA), a controlled substance inventory is typically required to be conducted annually. This is a regulatory requirement to ensure that all controlled substances are appropriately accounted for in various facilities, such as pharmacies, hospitals, and clinics. The inventory should be a complete and accurate count of all stocks on hand at the time of the inventory and must include the drug name, dosage form, strength, quantity, and date of the inventory.
For certain controlled substances, more frequent inventory checks, such as biannually or even on a monthly basis, may be mandated depending on the regulations of the state and the classification of the controlled substance. However, under federal law, the minimum requirement is an annual inventory. It is crucial for establishments that handle controlled substances to stay updated with their state and local regulations to ensure compliance.
To answer the student's question, the most common and federally required frequency for completing a controlled substance inventory is annually (option a), though more frequent inventories might be necessary depending on additional regulations.