The CSA places each controlled substance—drug or other substance –into one of five schedules based on the substance’s medical use, potential for abuse, and safety or dependence liability. The Act also allows substance to be added to or removed from a schedule, and to be rescheduled or transferred from one schedule to another. The basis upon which substances are placed into each of the five schedules is explained below, and examples of drugs’ or other substances within the schedules are listed.

Schedule I (CI) Substance

The controlled substances in this schedule are those that have no accepted medical use in the United States (U.S.), are not accepted as safe for use under medical supervision,and have a high abuse potential. Some examples are heroin, marijuana, LSD, peyote, mescaline, psilocybin, MDA, MDMA, ketobemidone, acetylmethadol, fenethylline, tilidine, methaqualone, and certain fentanyl and merperidine analogs.

Schedule II (CII) Substances

The controlled substances in this schedule have a high abuse potential with severe psychological or physical dependence liability, but have accepted medical use in the U.S. CII controlled substances consist of certain narcotic, stimulant, and depressant drugs. Some examples of CII narcotics are: opium, morphine, codeine, hydromorphone (Dilaudid)¹, methadone, meperidine (Demerol), cocaine, oxycodone (Percodan), anileridine (Lertine), the immediate precursor phenylacetone (P-2-P), and oxymorphine (Numorphan). Also in CII are the stimulants amphetamine (Dexedrine), methamphetamine (Desoxyn), phenmetrazine (Preludine), and methylphenidate (Ritalin); the depressants amobarbital, pentobarbital, secobarbital; and fentanyl (Sublimaze), etorphine hydrochloride, and phencyclidine (PCP).

Schedule III (CIII) Substances

The controlled substances in this schedule have an abuse potential and dependence liability less than those in CI and CIII, and have an accepted medical use in the U.S. They include preparations containing limited quantities of certain narcotic drugs, and other nonnarcotic drugs such as: derivatives of barbituric acid, except those that are listed in another schedule, glutethimide (Doriden), methyprylon (Noludar), nalorphine, benzphetamine, chlorphentermine, clortermine, and phendimetrazine.

Schedule IV (CIV) Substances

Schedule V (CV) Substances

The controlled substances in this schedule have an abuse potential and dependence liability less than those listed in CIV and have an accepted medical use in the U.S. They are often available without prescription, and include preparations containing limited quantities of certain narcotic drugs generally for antitussive and antidiarrheal purposes. Buprenorphine is also a CV drug.