What are the drug schedules?

To determine a drug’s use and its potential for abuse or medical use, the U.S. government created the Controlled Substances Act. The CSA categorizes drugs into different schedules, which, in turn, state the legal and medical status of the substances.

Currently, the CSA defines drugs in schedules I through V.

Schedule I drugs

Schedule I drugs have the highest potential for abuse and no accepted medical use. Examples include heroin, LSD and ecstasy. The law determines these drugs unsafe even under medical supervision. Manufacturing, distributing and possessing Schedule I drugs can result in criminal penalties.

Schedule II drugs

Schedule II drugs also have a high potential for abuse but have accepted medical uses. These drugs can lead to severe psychological or physical dependence. Examples include cocaine, methamphetamine and prescription painkillers like oxycodone and fentanyl.

Schedule III drugs

Schedule III drugs have accepted medical uses, and abusing them can create a moderate or low physical dependence and a high psychological dependence. Examples include ketamine, anabolic steroids and certain prescription medications containing codeine.

Schedule IV drugs

Schedule IV drugs have a lower potential for abuse relative to Schedule III drugs and have accepted medical uses. However, these drugs can lead to limited psychological or physical dependence. Examples include prescription medications like Xanax, Valium and Ativan.

Schedule V drugs

Schedule V drugs have the lowest potential for abuse among the scheduled drugs and have accepted medical uses. These drugs typically contain limited quantities of certain narcotics. Examples include cough medications containing less than 200 milligrams of codeine per 100 milliliters, such as Robitussin AC and medications for diarrhea and pain relief.

Each schedule regulates drugs appropriately based on their potential for harm and benefit to society. The drug schedules also figure into penalties for the use or possession of these substances.