Drug Facts – Marijuana


Marijuana is a green, brown, or gray mixture of dried, shredded leaves, stems, seeds, and flowers of the hemp plant (Cannabis sativa). Cannabis is a term that refers to marijuana and other drugs made from the same plant. Other forms of cannabis include sinsemilla, hashish, and hash oil. All forms of cannabis are mind-altering (psychoactive) drugs.

The main active chemical in marijuana is THC (delta-9-tetrahydrocannabinol). Short-term effects of marijuana use include problems with memory and learning, distorted perception, difficulty in thinking and problem solving, loss of coordination, increased heart rate, and anxiety.

Marijuana is usually smoked as a cigarette (called a joint) or in a pipe or bong. Marijuana has also appeared in blunts, which are cigars that have been emptied of tobacco and refilled with marijuana, sometimes in combination with another drug, such as crack. It can also be mixed into foods or used to brew a tea.

Extent of Use

Marijuana is the most commonly used illicit drug. According to the 2008 National Survey on Drug Use and Health (NSDUH), an estimated 102 million Americans aged 12 or older have tried marijuana at least once in their lifetimes, representing 41% of the U.S. population in that age group. The number of past year marijuana users in 2008 was approximately 25.8 million (10.3% of the population aged 12 or older) and the number of past month marijuana users was 15.2 million (6.1%).

Among 12-17 year olds surveyed as part of the 2008 NSDUH, 6.7% reported past month marijuana use. Additional NSDUH results indicate that 16.5% of 18-25 year olds and 4.2% of those aged 26 or older reported past month use of marijuana.

In 2008, there were 2.2 million persons aged 12 or older who had used marijuana for the first time within the past 12 months; this averages to about 6,000 initiates per day. This estimate was about the same as the estimate in 2007 (2.1 million) and 2002 (2.2 million).

A 2002 SAMHSA report, Initiation of Marijuana Use: Trends, Patterns and Implications, concludes that the younger children are when they first use marijuana, the more likely they are to use cocaine and heroin and become dependent on drugs as adults. The report found that 62% of adults age 26 or older who initiated marijuana before they were 15 years old reported that they had used cocaine in their lifetime. More than 9% reported they had used heroin and 53.9% reported non-medical use of psychotherapeutics. This compares to a 0.6% rate of lifetime use of cocaine, a 0.1% rate of lifetime use of heroin and a 5.1% rate of lifetime non-medical use of psychotherapeutics for those who never used marijuana. Increases in the likelihood of cocaine and heroin use and drug dependence are also apparent for those who initiate use of marijuana at any later age.

Results of the 2008 Monitoring the Future survey indicate that 14.6% of eighth graders, 29.9% of tenth graders, and 42.6% of twelfth graders reported lifetime use of marijuana. In 2007, these percentages were 14.2%, 31.0%, and 41.8%, respectively.

Approximately 72.0% of eighth graders, 64.8% of tenth graders, and 51.7% of twelfth graders surveyed in 2008 reported that smoking marijuana regularly was a “great risk.”

The Youth Risk Behavior Surveillance System (YRBSS) study by the Centers for Disease Control and Prevention (CDC) surveys high school students on several risk factors including drug and alcohol use. Results of the 2007 survey indicate that 38.1% of high school students reported using marijuana at some point in their lifetimes. Additional YRBSS results indicate that 19.7% of students surveyed in 2007 reported current (past month) use of marijuana.

Approximately 47.5% of college students and 56.7% of young adults (ages 19–28) surveyed in 2007 reported lifetime use of marijuana.

According to data from the Bureau of Justice Statistics, approximately 77.6% of State prisoners and 71.2% of Federal prisoners surveyed in 2004 indicated that they used marijuana/hashish at some point in their lives.

Health Effects

Marijuana abuse is associated with many detrimental health effects. These effects can include respiratory illnesses, problems with learning and memory, increased heart rate, and impaired coordination. A number of studies have also shown an association between chronic marijuana use and increased rates of anxiety, depression, suicidal ideation, and schizophrenia. Long-term marijuana abuse can lead to addiction. Studies conducted on both people and animals suggest marijuana abuse can cause physical dependence. Withdrawal symptoms may include irritability, sleeplessness, decreased appetite, anxiety, and drug craving.

Someone who smokes marijuana regularly may have many of the same respiratory problems that tobacco smokers do, such as daily cough and phlegm production, more frequent acute chest illnesses, a heightened risk of lung infections, and a greater tendency toward obstructed airways. Cancer of the respiratory tract and lungs may also be promoted by marijuana smoke. Marijuana has the potential to promote cancer of the lungs and other parts of the respiratory tract because marijuana smoke contains 50 percent to 70 percent more carcinogenic hydrocarbons than does tobacco smoke.

Marijuana’s damage to short-term memory seems to occur because THC alters the way in which information is processed by the hippocampus, a brain area responsible for memory formation. In one study, researchers compared marijuana smoking and nonsmoking 12th-graders’ scores on standardized tests of verbal and mathematical skills. Although all of the students had scored equally well in 4th grade, those who were heavy marijuana smokers, i.e., those who used marijuana seven or more times per week, scored significantly lower in 12th grade than nonsmokers. Another study of 129 college students found that among heavy users of marijuana critical skills related to attention, memory, and learning were significantly impaired, even after they had not used the drug for at least 24 hours.

Of an estimated 113 million emergency department (ED) visits in the U.S. during 2006, the Drug Abuse Warning Network (DAWN) estimates that 1,742,887 were drug-related. DAWN data indicate that marijuana was involved in 290,563 ED visits.


From 1997 to 2007, the number of admissions to treatment in which marijuana was the primary drug of abuse increased from 197,840 in 1997 to 287,933 in 2007. The marijuana admissions represented 12.3% of the total drug/alcohol admissions to treatment during 1997 and 15.8% of the treatment admissions in 2007. The average age of those admitted to treatment for marijuana during 2007 was 24 years.

Arrests & Sentencing

According to the Federal Bureau of Investigation’s Uniform Crime Reporting Program, there were an estimated total of 1,841,182 state and local arrests for drug abuse violations in the United States during 2007. Of these drug abuse violation arrests, 5.3% were for the sale/manufacture of marijuana and 42.1% were for marijuana possession.

According to the National Drug Intelligence Center there were 5,039 Federal marijuana-related arrests during 2006. This is down from the 5,599 such arrests during 2005.

According to a 2004 Bureau of Justice Statistics survey of state and Federal prisoners, approximately 12.7% of state prisoners and 12.4% of Federal prisoners were serving time for a marijuana-related offense. This is a decrease from 1997 when the figures were 12.9% and 18.9%, respectively.

During FY 2008, there were 6,337 Federal offenders sentenced for marijuana-related charges in U.S. Courts. Approximately 97.8% of these cases involved trafficking and 1.6% of cases involved simple possession.

The Arrestee Drug Abuse Monitoring (ADAM) II program is designed to gather information on drug use and related matters from adult male offenders within 48 hours of arrest. ADAM II serves as a critical source of data for estimating trends in drug use in local areas, understanding the relationship between drugs and crime, and describing drug market activity in the adult male arrestee population in 10 U.S. sites during 2008. In 9 out of the 10 sites, 45% or more of the arrestees reported using marijuana within the past year.

Production & Trafficking

The threat associated with marijuana trafficking and abuse is rising, which is largely the result of a growing demand for high-potency marijuana and a related increase in the drug’s availability. An increase in domestic cannabis cultivation by drug trafficking organizations contributes to this threat, particularly the recent expansion of cultivation operations by Mexican, Asian and Cuban organizations.

Most foreign-source marijuana smuggled into the United States enters through or between points of entry at the U.S.-Mexico border. During 2006, 1,115,710 kilograms of marijuana were seized along the Southwest Border. Cannabis cultivation in Mexico remains high and most of the marijuana produced in that country is destined for U.S. drug markets.

Domestic Cannabis Eradication/Suppression Program (DCE/SP) data indicate that a total of 5,231,658 marijuana plants were seized in the U.S. during 2006. This is up from 4,209,086 plants seized during 2005. The recent increases in cannabis cultivation and marijuana production within the United States coincide with the continued flow of marijuana from foreign sources, which may lead to market saturation in major markets. This saturation could reduce the price of the drug significantly.

According to combined 2002, 2003 and 2004 NSDUH data, more than three fourths (78.2%) of the past year marijuana users aged 18 to 25 bought their most recently used marijuana from a friend. The majority (56.0%) of past year marijuana users aged 18 to 25 bought their most recently used marijuana inside a home, apartment or dormitory.


Marijuana is a Schedule I substance under the Controlled Substances Act (CSA). Schedule I drugs are classified as having a high potential for abuse, no currently accepted medical use in treatment in the United States, and a lack of accepted safety for use of the drug or other substance under medical supervision.

In the case of United States v. Oakland Cannabis Club the U.S. Supreme Court ruled that marijuana has no medical value as determined by Congress. The opinion of the court stated that: “In the case of the Controlled Substances Act, the statute reflects a determination that marijuana has no medical benefits worthy of an exception outside the confines of a government-approved research project.” The case reached the U.S. Supreme Court after the federal government sought an injunction in 1998 against the Oakland Cannabis Buyers Cooperative and five other marijuana distributors in California.

The United States Court of Appeals for the District of Columbia Circuit issued a ruling on May 24, 2002, upholding DEA’s determination that marijuana must remain a schedule I controlled substance. The Court of Appeals rejected an appeal that contended that marijuana does not meet the legal criteria for classification in schedule I, the most restrictive schedule under the Controlled Substances Act.

Street Terms

Term Definition
420 Marijuana use; the time in which to smoke
BC Bud High-grade marijuana from Canada
Bud Marijuana
Chronic Marijuana
Dope Marijuana
Ganja Marijuana; Jamaican term
Herb Marijuana
HOmegrown Marijuana
Hydro Marijuana grown in water (hydroponically)
Indo Marijuana from Northern California
Kind Bud High quality marijuana
Mary Jane Marijuana
Shake Marijuana; usually then end of one’s stash
Sinsemilla Potent marijuana

Taken from the Office of National Drug Control Policy Website.