Federal law requires pharmacies to conduct inventory control on controlled substances every ___ years?

• A. Two years
• B. One year
• C. Three years
• D. Four years

Answer: (A)

A biennial inventory is required for controlled substances under federal law. Pharmacies must keep an exact, up-to-date count of all controlled substances on hand, and this inventory must be conducted at least every two years after the initial inventory when the registration is first established. This cadence helps ensure accurate records, detect discrepancies, and deter diversion, which is why two years is the correct interval. While some day-to-day tracking may use perpetual counts for certain schedules, the federal minimum standard for the overall inventory is every two years. An annual count would be more frequent than required, whereas extending beyond two years would fail to meet the mandated biennial schedule.