Schedules of Controlled Substances

Controlled substances are drugs which have a potential for abuse. They are classified by the U.S. Controlled Substances Act of 1970 and the individual state laws into five schedules according to three basic considerations:

  1. the degree of potential for abuse;

  2. whether the substance has currently accepted medical use; and

  3. whether the use under medical circumstances is considered safe(7). The schedules are known as schedule I, II, III,  IV, V, schedule I being the most restrictive and V the least restrictive. Schedule I substances have no accepted medical uses and are illegal (heroin, LSD, marijuana); schedules II, III, IV, and V have accepted medical uses and generally have Food and Drug Administration (FDA) approval for medical use. Schedule II substances can be narcotic or non-narcotic. Schedule II narcotics include morphine, methadone, hydromorphone, and oxycodone.(8)

Glossary Footer

  1. International Narcotics Control Board. 1961 Single Convention on Narcotic Drugs: Part 1: The International Control System for Narcotic Drugs. Vienna, Austria: International Narcotics Control Board, 2005. (Available at
  2. World Health Organization. Achieving balance in national opioids control policy: Guidelines for assessment. Geneva, Switzerland: World Health Organization, 2000.
  3. Morgan JP. American opiophobia: Customary underutilization of opioid analgesics. In: Hill CS, Fields WS, eds. Advances in Pain Research and Therapy, Volume 11. vol. 11. New York, NY: Raven Press, 1989:181-189. 
  4. Bennett DS, Carr DB. Opiophobia as a barrier to the treatment of pain. J Pain Palliat Care Pharmacother 2002;16:105-109.
  5. International Association for the Study of Pain. International Association for the Study of Pain Web site.
  6. World Health Organization. National cancer control programmes: policies and managerial guidelines. Second ed. Geneva, Switzerland: World Health Organization, 2002. (Available at
  7. Controlled Substances Act, 812, Schedules of controlled substances. 
  8. District Court of Appeal of Florida, Third District.676 So.2d 1380, June 26, 1996.
  9. World Health Organization. WHO expert committee on drug dependence: thirty-fourth report. Geneva, Switzerland: World Health Organization, 2006. (Available at

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