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Controlled Substances Act

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The Controlled Substances Act

The Controlled Substances Act (CSA) went into effect in 1971. It established five schedules that classify controlled substances according to how dangerous they are, their potential for abuse and addiction, and whether they possess legitimate medical value. The CSA for 47 years has provided the legal framework from which DEA derives its authority. To learn more, please visit the Diversion Control Division section of this website.

The Controlled Substances Act (CSA) places all substances which had previously been regulated under existing federal law into one of five schedules. This placement is based upon the substance’s medical use, potential for abuse, and safety or dependence liability. More information can be found in Title 21 United States Code (USC) Controlled Substances Act.

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United States Drug Enforcement Administration DEA.gov is an official site of the U.S. Department of Justice