The drug policy in the United States is the activity of the federal government relating to the regulation of drugs. Starting in the early 1900s, the United States government began enforcing drug policies. These policies criminalized drugs such as opium, morphine, heroin, and cocaine outside of medical use. The drug policies put into place are enforced by the Food and Drug Administration and the Drug Enforcement Administration. Classification of Drugs are defined and enforced using the Controlled Substance Act, which lists different drugs into their respective substances based on its potential of abuse and potential for medical use. Four different categories of drugs are Alcohol, Cannabis, Opioids, and Stimulants.

The Controlled Substances Act (CSA) is the statute establishing federal U.S. drug policy under which the manufacture, importation, possession, use, and distribution of certain substances is regulated. It was passed by the 91st United States Congress as Title II of the Comprehensive Drug Abuse Prevention and Control Act of 1970 and signed into law by President Richard Nixon. The Act also served as the national implementing legislation for the Single Convention on Narcotic Drugs.