Controlled Substance Act

The Comprehensive Drug Abuse Prevention and Control Act; a law enacted in 1970 to control the distribution and use of all depressant and stimulant drugs and other drugs of abuse or potential abuse as may be designated by the Drug Enforcement Administration (DEA) of the Department of Justice.
The act specifies record keeping by the pharmacist, the format for prescription writing, and the limit on the amount of a drug that can be legally dispensed. This limit and whether refills are allowed vary with the nature of the drug. Centrally acting drugs (such as narcotics, stimulants, and certain sedatives) are divided into five classes called schedules I through V. Schedule I drugs are experimental. Prescriptions for schedule II drugs may not be refilled. Prescriptions for schedule III and IV drugs may be refilled up to five times within 6 months of the time the initial prescription was written. Schedule V drugs are restricted only to the extent that all nonscheduled prescription drugs are regulated.

Controlled substances are labeled with a large C followed by the Roman numeral designation. Alternatively, the Roman numeral is within the large C.