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Summary Article: Medical Marijuana
from Encyclopedia of Drug Policy: "The War on Drugs" Past, Present, and Future

Marijuana, the popular name for cannabis, has been used as a medicine since ancient times. In modern times, medical marijuana has become a political issue as a growing number of U.S. states have moved to legalize its availability even while federal law prohibits it as a Schedule I drug (meaning it has no accepted medical use). Recent years have seen mounting scientific evidence of marijuana's effectiveness for a broad range of conditions and growing use by patients and doctors. However, the U.S. government has resisted changing its Schedule I status.

Cannabis is mentioned in the earliest pharmaceutical texts of the ancient world. Introduced to Western medicine by Dr. William O'Shaughnessy in 1839, it was widely prescribed during the 19th century for conditions including migraines, neuralgia, spasticity, and menstrual cramps. Medical interest declined with the introduction of more potent narcotics toward the end of the century. Until modern times, cannabis was regularly administered in oral preparations. The dosage of these medications was difficult to gauge, as the major active ingredient, THC (tetrahydrocannabinol) was not identified until 1965. Other active ingredients, notably the THC congeners known as cannabinoids, have been identified in marijuana.

Cannabis was exempted from the Harrison Act at the urging of pharmaceutical manufacturers, who argued that it was safe and rarely abused. It was removed from the market under the Marihuana Tax Act of 1937 over the objections of the American Medical Association. Following passage of the Controlled Substances Act (1970), marijuana was temporarily classified as a Schedule I drug with the intent of revisiting this classification after the report of the Presidential Commission on Marijuana (1972); however, this never happened.

Marijuana's medical effects were rediscovered serendipitously by young chemotherapy and glaucoma patients in the 1970s. In 1972 the National Organization for Reform of Marijuana Laws filed a petition to reschedule marijuana as a Schedule II prescription drug. After prolonged hearings, the Drug Enforcement Administration (DEA) overruled the recommendation of its own administrative judge that marijuana be rescheduled in 1988, ruling that it must first be proven effective in controlled clinical studies.

In 1976 Robert Randall, a glaucoma patient, successfully sued the government to supply him marijuana from its own research farm through a special “compassionate use” FDA protocol. A few other patients qualified for the program before it was closed to new entrants in 1991 due to a flood of new applications. A synthetic marijuana pill known as Marinol (dronabinol) was approved by the FDA in 1986 as an antinauseant. Marinol differs from marijuana in that it contains only one active ingredient (THC) and must be ingested orally. Oral ingestion acts more slowly and unpredictably than inhalation and delivers a different metabolite of THC to the body.

Medical marijuana emerged as a political issue when San Francisco voters overwhelmingly approved a medical marijuana ballot measure, Proposition P (1991). Shortly afterward, the first medical cannabis dispensary opened in San Francisco, purveying marijuana to members with a doctor's note. In 1996 California voters approved a landmark medical marijuana initiative, Proposition 215, which legalized the possession and cultivation of marijuana by patients and caregivers given a physician's recommendation. Boosted by opinion polls showing 70 percent public support for medical marijuana, similar laws were adopted in other states (14 states plus the District of Columbia to date).

Medical marijuana labeled for use under California state law. In the United States, up to 1 or 2 percent of the adult population, or over 400,000 people, are using medical marijuana under such laws.

Although Prop 215 did not explicitly legalize sales or distribution, it provided implicit protection for patients to organize collective gardens and dispensaries. The U.S. Justice Department obtained a court injunction to close six dispensaries in 1998, a move that was upheld by the Supreme Court in United States v. Oakland Cannabis Buyers' Cooperative in 2001. Subsequently, two patients sued to have the federal law declared unconstitutional, claiming that the Congress lacked power to prohibit their personal medical use of marijuana under the interstate commerce clause. In a 6-3 decision, the court upheld the federal ban (Gonzalez v. Raich, 2005). Despite these decisions and DEA efforts to enforce them, dispensaries continued to proliferate. Over 100 federal cases have been filed against medical marijuana providers, prompting complaints of federal interference in state laws.

In 1999 the Institute of Medicine reported that marijuana and its ingredients had medical benefits. It recommended further research, with emphasis on nonsmoked alternatives. Although no federal research was undertaken, California established a Center for Medicinal Cannabis Research, which reported finding marijuana therapeutically effective in five clinical studies by 2010. Since 1975, over 110 controlled studies have been published on cannabis and cannabinoids for a wide range of indications including nausea, appetite loss, chronic pain, spasticity, MS, migraines, gastrointestinal disorders, glaucoma, and mental disorders. However, none have been FDA approval studies. Current federal policy precludes FDA approval of marijuana. The only legal, DEA-licensed source of marijuana for researchers is a garden operated by the National Institute on Drug Abuse, which has refused to develop it for medical use. In 2007 the DEA denied an application by the University of Massachusetts to establish an independent facility for medical marijuana research, overruling the recommendation of a DEA administrative law judge.

Elsewhere, medical marijuana is legally available in Canada, Israel, and the Netherlands, and a marijuana-based extract is under development in the United Kingdom. In the United States, over 400,000 patients are using medical marijuana under state laws, or up to 1 to 2 percent of the adult population. Critics have objected that many lack true medical need because state laws are too lax about allowing recommendations. The Justice Department has stated that its policy is not to arrest patients, but large-scale distributors and profiteers. In 2009 the Justice Department announced that it would no longer pursue defendants who are compliant with state laws, but federal law remains unchanged.

See Also:

California Laws and Programs, Drug Enforcement Administration, Gonzales v. Raich (2005), Marihuana Tax Act (1937), Marijuana, National Commission on Marihuana and Drug Abuse (1972), National Organization for the Reform of Marijuana Laws, Obama Administration, Barack.

Further Readings
  • Bock, Alan. Waiting to Inhale: The Politics of Medical Marijuana. Santa Ana, CA: Seven Locks Press, 2000.
  • Grinspoon, L., et al. Marihuana, the Forbidden Medicine. New Haven, CT: Yale University Press, 1997.
  • Hazekamp, Arno and Franjo, Grotenhermen. “Review on Clinical Studies With Cannabis and Cannabinoids 2005-2009.” Cannabinoids, v.5: 2010.
  • National Institute of Medicine. Marijuana and Medicine: Assessing the Science Base. Washington, DC: National Academy Press1999.
  • Gieringer, Dale H.
    Independent Scholar
    Copyright © 2011 by SAGE Publications, Inc.

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