Controlled Substance Schedules
The Controlled Substances Act (CSA) classifies drugs into five schedules (I-V) based on their accepted medical use, abuse potential, and potential for physical or psychological dependence. Pharmacy technicians must understand the differences between schedules, the rules governing each, and proper handling procedures.
Schedule Overview
| Schedule | Abuse Potential | Medical Use | Dependence Potential | Examples |
|---|---|---|---|---|
| Schedule I (C-I) | Highest | No currently accepted medical use in the US | Severe | Heroin, LSD, psilocybin, MDMA (ecstasy) |
| Schedule II (C-II) | High | Accepted with severe restrictions | Severe physical or psychological | Oxycodone, morphine, fentanyl, amphetamine, methylphenidate, methadone, hydromorphone |
| Schedule III (C-III) | Moderate | Accepted | Moderate to low physical, high psychological | Testosterone, buprenorphine, ketamine, anabolic steroids |
| Schedule IV (C-IV) | Lower | Accepted | Limited | Alprazolam, lorazepam, diazepam, zolpidem, tramadol, carisoprodol |
| Schedule V (C-V) | Lowest | Accepted | Limited | Pregabalin, lacosamide, certain cough preparations with small amounts of codeine |
Prescribing and Dispensing Rules
| Rule | C-II | C-III to C-V |
|---|---|---|
| Prescription required? | Yes - written, electronic, or oral in emergency | Yes - written, electronic, oral, or faxed |
| Refills allowed? | No refills permitted | Up to 5 refills within 6 months from date written |
| Transfer of prescription? | Not transferable | One-time transfer permitted (except pharmacies sharing a real-time database) |
| Partial fill? | Allowed; remainder must be filled within 72 hours (community). Long-term care and terminal patients may receive partial fills for up to 60 days. | Allowed within the 6-month period |
| Emergency oral C-II? | Permitted if prescriber provides written/electronic Rx within 7 days | N/A - oral Rx routinely permitted |
DEA Number Validation
Every prescriber of controlled substances must have a valid DEA registration number. Pharmacy technicians should know how to verify a DEA number:
DEA Number Format: Two letters followed by seven digits (e.g., AB1234563)
- First letter: Indicates registrant type (A, B, or F for general practitioners; M for mid-level practitioners)
- Second letter: First letter of the prescriber's last name
- Check digit validation:
- Add the 1st, 3rd, and 5th digits together
- Add the 2nd, 4th, and 6th digits together, then multiply that sum by 2
- Add both results together
- The last digit of this total should equal the 7th digit of the DEA number
Worked Example: DEA # AB1234563
- Odd positions: 1 + 3 + 5 = 9
- Even positions: (2 + 4 + 6) x 2 = 12 x 2 = 24
- Sum: 9 + 24 = 33
- Last digit of 33 = 3 = 7th digit of DEA number. Valid.
DEA Forms
| Form Number | Purpose |
|---|---|
| DEA Form 222 | Ordering Schedule II controlled substances (triplicate or electronic - CSOS) |
| DEA Form 41 | Destruction/disposal of controlled substances |
| DEA Form 106 | Reporting theft or significant loss of controlled substances |
| DEA Form 224 | New registration for dispensing (pharmacies, hospitals) |
| DEA Form 224a | Renewal of DEA registration |
Storage and Security Requirements
- All controlled substances must be stored in a securely locked, substantially constructed cabinet or safe, or dispersed throughout non-controlled inventory in a manner that deters diversion.
- Schedule II substances are most commonly stored in a locked safe or vault with limited access.
- Access should be restricted to authorized personnel only.
- Perpetual inventory is recommended (and often required by state law) for C-II medications.
- Physical inventory of all controlled substances must be conducted at least every two years (biennial inventory), as required by the DEA.
- Exact counts are required for C-II drugs during inventory; estimated counts may be used for C-III through C-V if the container holds 1000 or fewer dosage units.
Recordkeeping
- All controlled substance records must be maintained for a minimum of 2 years (federal requirement; some states require longer).
- Records for C-II must be maintained separately from all other records.
- Records for C-III through C-V must be readily retrievable from other prescription records.
- Invoices for C-II orders (DEA 222 forms) serve as the receipt record and must be kept on file.
Disposal and Reverse Distribution
- Expired or unwanted controlled substances cannot simply be thrown away.
- Pharmacies must use a DEA-registered reverse distributor or follow DEA-authorized destruction procedures.
- Two witnesses are generally required for in-pharmacy destruction, and documentation must be maintained.
- DEA Form 41 is used to document destruction.
Corresponding Responsibility
Both the prescriber and the pharmacist share "corresponding responsibility" to ensure a controlled substance prescription is issued for a legitimate medical purpose. Pharmacy technicians should alert the pharmacist if a prescription appears suspicious (e.g., early refills, unusual quantities, cash-only payments for high-dose opioids, multiple prescribers).
Exam Tips
- Know the DEA number validation method - it appears frequently on exams.
- Remember: C-II = no refills; C-III through C-V = up to 5 refills in 6 months.
- DEA Form 222 is specifically for ordering C-II substances.
- DEA Form 106 is for reporting theft or loss.
- The biennial inventory is required by federal law every 2 years.
- Tramadol (C-IV) and pregabalin (C-V) are commonly tested schedule questions because students often forget their schedules.