Controlled Substance
A controlled substance refers to a drug or chemical whose manufacture, possession, or use is regulated by law. These regulations are primarily due to the drug’s potential for abuse or addiction, as well as its accepted medical use.

Key Takeaways
- Controlled substances are regulated due to their potential for abuse and dependency.
- The US Drug Enforcement Administration (DEA) classifies these substances into five schedules based on their medical use and abuse potential.
- Schedule I drugs have no accepted medical use and a high potential for abuse, while higher schedules indicate decreasing abuse potential and increasing medical acceptance.
- The primary federal law governing these substances in the U.S. is the Controlled Substances Act (CSA).
- Both federal and state laws regulate controlled substances, with state laws often mirroring or being stricter than federal guidelines.
What is a Controlled Substance?
A controlled substance is a drug or chemical that is subject to government regulation. These regulations are put in place because these substances have a potential for abuse or addiction, even if they possess legitimate medical applications. Understanding what are controlled substances involves recognizing their dual nature: some are vital medications, while others pose significant public health risks due to their psychoactive effects.
Purpose of Control
The primary purpose of control over these substances is to protect public health and safety. By regulating their production, distribution, and use, authorities aim to prevent misuse, diversion, and illicit trafficking. This control helps to mitigate the societal harms associated with drug abuse, including addiction, crime, and adverse health outcomes. The stringent oversight ensures that medically necessary drugs are available under controlled conditions, while those with high abuse potential and no accepted medical use are strictly prohibited.
Classification and Types of Controlled Drugs
The classification system for types of controlled drugs is crucial for determining the level of regulation applied to each substance. In the United States, the Drug Enforcement Administration (DEA) categorizes controlled substances into five schedules, or categories, based on their accepted medical use and their potential for abuse or dependence. This controlled substance classification system dictates the legal framework for their handling, from manufacturing to prescription and possession.
| Schedule | Abuse Potential | Accepted Medical Use | Examples |
|---|---|---|---|
| Schedule I | High | None | Heroin, LSD, MDMA (ecstasy), marijuana (federally) |
| Schedule II | High | Yes, with severe restrictions | Oxycodone, fentanyl, Adderall, cocaine, methamphetamine |
| Schedule III | Moderate to low physical dependence or high psychological dependence | Yes | Tylenol with codeine, ketamine, anabolic steroids, buprenorphine |
| Schedule IV | Low | Yes | Xanax, Valium, Ambien, Ativan |
| Schedule V | Lowest | Yes | Cough syrups with codeine (e.g., Robitussin AC), Lyrica |
Schedule I: High Abuse Potential
Substances in Schedule I are characterized by a high potential for abuse and currently have no accepted medical use in treatment in the United States. They also lack accepted safety for use under medical supervision. Examples include heroin, lysergic acid diethylamide (LSD), and MDMA (ecstasy). Federally, marijuana is also classified as a Schedule I substance, despite its legal status for medical or recreational use in many states.
Schedule II: High Abuse Potential with Medical Use
Drugs in Schedule II have a high potential for abuse, which may lead to severe psychological or physical dependence. However, unlike Schedule I substances, they have a currently accepted medical use in treatment in the U.S. Examples include potent opioid painkillers such as oxycodone (OxyContin), fentanyl, and stimulants like amphetamine (Adderall) and methylphenidate (Ritalin).
Schedule III: Moderate Abuse Potential
Schedule III substances have a potential for abuse less than Schedule I or II drugs. Abuse of these substances may lead to moderate or low physical dependence or high psychological dependence. They have a currently accepted medical use. Examples include products containing less than 90 milligrams of codeine per dosage unit (e.g., Tylenol with codeine), ketamine, and anabolic steroids.
US Laws Governing Controlled Substances
The legal framework surrounding controlled substance laws US is comprehensive, involving both federal and state statutes designed to regulate and control these drugs. These laws aim to balance the need for legitimate medical use with the imperative to prevent diversion and abuse, thereby protecting public health and safety.
The Controlled Substances Act (CSA)
The primary federal law governing controlled substances in the United States is The Controlled Substances Act (CSA), enacted in 1970. The CSA places all substances that are regulated under federal law into one of five schedules based on their medical use, potential for abuse, and safety or dependence liability. It provides the legal basis for the DEA to regulate the manufacture, importation, possession, use, and distribution of narcotics, stimulants, depressants, hallucinogens, anabolic steroids, and other chemicals.
Federal vs. State Regulations
While the CSA provides a nationwide framework, both federal vs. state regulations play a significant role. State laws often mirror the federal scheduling system but can also impose stricter controls or additional regulations. For instance, a state might classify a substance in a more restrictive schedule than the federal government, or implement more stringent prescribing guidelines. However, state laws cannot be less restrictive than federal law. This dual regulatory system means that individuals and entities dealing with controlled substances must comply with both federal and applicable state laws, ensuring a robust and layered approach to drug control.























