Controlled Substances: Scheduling, Prescribing, Dispensing, and Monitoring
Scheduling and registration
Controlled substances are placed in Schedules I-V under the CSA based on abuse potential and accepted medical use. Schedule I has no accepted medical use; Schedules II-V have progressively less abuse potential. Federal scheduling is a floor, and Minnesota may place a substance in a stricter state schedule. Pharmacies and prescribers need a DEA registration, and practitioners must be authorized under state law. DEA Form 222 (or CSOS) is used to order Schedule II substances; it is not a prescription form.
Prescription rules
Schedule II prescriptions require a written, electronic, or qualifying emergency oral order; no refills are permitted. Emergency oral Schedule II orders require a written/electronic follow-up within 7 days. Schedules III-V may be refilled up to five times within six months of issuance. Partial fills are limited but permitted for Schedule II under specific conditions (e.g., long-term care, terminal illness, or patient/prescriber/pharmacist inability to supply). Prescribers and pharmacists share corresponding responsibility for legitimacy. Minnesota's Prescription Monitoring Program (PMP) requires dispensers to report controlled substance dispensing; check PMP data as part of due diligence.
Traps
Questions test refill limits, partial-fill rules, and whether a mid-level practitioner may prescribe a given schedule. A common error is accepting refills on a Schedule II prescription or treating a 222 form as a prescription. Another is ignoring a state schedule that is stricter than federal.
Worked example
A Schedule II prescription for 90 tablets states "refill 2 times." The refills are invalid. Dispense up to the valid quantity after verifying the prescriber and patient, and do not refill.