ONDCP seeks to foster healthy individuals and safe communities by effectively 

leading the Nation’s effort to reduce drug use and its consequences.

October 2010 

Marijuana: Know the Facts

Marijuana is a common drug made from the dried, shredded leaves, flowers, and other parts of 

a plant in the genus Cannabis. The term cannabis generally refers to marijuana and other drugs 

made from the same plant, including sinsemilla, hashish, and hash oil. 

Marijuana is the most commonly 

used illicit drug. Although 

marijuana is sometimes 

characterized as a “harmless 

herb,” the cultivation, trafficking, 

and use of the drug have a 

negative impact on many aspects 

of our lives, from public health to

national security, transportation, 

the environment, and educational 

attainment. 

The Obama Administration, 

together with Federal partners 

and State and local officials, is 

working to reduce the use of 

marijuana and other illicit drugs 

through development of 

strategies that more fully integrate the principles of prevention, treatment, and recovery.

National Trends

♦ Rates of marijuana use among 8th, 10th, and 12th graders are higher than rates for any 

other illicit drug.1

♦ According to the 2009 National Survey on Drug Use and Health (NSDUH), 16.7 million 

people age 12 or older were current marijuana users, meaning they used the drug during 

the month prior to taking the survey (see chart, above).2

♦ NSDUH also shows that from 2008 to 2009, the rate of current illicit drug use among 

young adults aged 18 to 25 climbed 8 percent, from 19.6% to 21.2%, driven largely by a 

10 percent rise in marijuana use (from 16.5% to 18.1%).3

♦ In 2009, there were 2.4 million new past-year users of marijuana. The average age of 

initiation dropped from 17.8 in 2008 to 17.0 in 2009.4

♦ The average potency of marijuana has more than doubled since 1998.5
ONDCP seeks to foster healthy individuals and safe communities by effectively 

leading the Nation’s effort to reduce drug use and its consequences.

October 2010 

Health Effects

Marijuana is classified as a Schedule I drug, meaning it has a high potential for abuse and no 

currently accepted medical use in treatment in the United States.6 In recent decades, marijuana 

growers have been genetically altering their plants to increase the percentage of delta-9-

tetrahydrocannabinol (THC), the main active ingredient in marijuana. The average potency of 

tested marijuana from Federal seizures more than doubled from 1998 to 2008,7

 as shown at 

left. 

THC acts upon 

specific sites in the 

brain called 

cannabinoid 

receptors, triggering 

a series of cellular 

reactions that 

ultimately lead to the 

“high” users 

experience when 

they smoke the drug.8

Marijuana 

intoxication can cause 

distorted 

perceptions, impaired 

coordination, 

difficulty in thinking 

and problem solving, 

and problems with learning and memory.9

 Studies have shown an association between chronic 

marijuana use and increased rates of anxiety, depression, suicidal thoughts, and 

schizophrenia.10 Other research has shown marijuana smoke to contain carcinogens and to be 

an irritant to the lungs. In fact, marijuana smoke contains 50-70 percent more carcinogenic 

hydrocarbons than does tobacco smoke.11

Prevention

To reduce the prevalence of marijuana, particularly among youth, the Federal Government is 

implementing multi-sector, community-based methods of prevention and intervention, such as 

the Drug Free Communities (DFC) program, the Screening, Brief Intervention, and Referral to 

Treatment (SBIRT) model, and the National Youth Anti-Drug Media Campaign. 

The DFC program strengthens collaboration efforts among prevention organizations to develop 

evidence- and community-based prevention strategies.12 The SBIRT model also uses a 

community-based approach to deliver individualized intervention materials for non-dependent 

marijuana users.13 SBIRT programs, which have screened more than 536,000 individuals for 

marijuana and other drug use, can operate in a variety of locations, such as trauma centers and 

schools.14 The ability to develop prevention materials that are community based and 

individually tailored is one of the most important characteristics of the DFC and SBIRT models. 
ONDCP seeks to foster healthy individuals and safe communities by effectively 

leading the Nation’s effort to reduce drug use and its consequences.

October 2010 

Trends in Perceived Harmfulness of

Smoking Marijuana Regularly

12/2009 Source: 2009 Monitoring the Future study (December 2009).

Statistically 

significant 

decreases from 

2008 to 2009

The National Youth Anti-Drug Media Campaign increases teen exposure to anti-drug messages 

through its Above the Influence program, which delivers prevention messaging at the national 

level and through more targeted efforts at the local community level. 

Also vital to the success of prevention programs are grants, such as the Strategic Prevention 

Framework State Incentive Grant, which provides funds to State, local, and tribal 

organizations.15

Youth at Risk

Marijuana use by teens has been shown to have a profoundly negative effect on their 

development.16 Results of the 2009 NSDUH study indicate that more than 3.3 million 12- to 17-

year-olds were past-year marijuana users, and that 830,000 youths in that age group displayed 

the characteristics of 

marijuana dependence or 

abuse in the past year.17

The downward trend in 

youth marijuana use during 

the late 1990s has ended.18

In 2009, according to NSDUH, 

the rate of past-month 

marijuana use among 12- to 

17-year-olds climbed to 

7.3%.19 This is significantly 

higher than the rate (6.7%) in 

2006, 2007, and 2008. 

A possible correlation with 

this phenomenon is that 

fewer young people today 

see “great risk” in using marijuana regularly (see chart, above). In 1991, approximately 80 

percent of 8th, 10th, and 12th graders perceived there to be “great risk” in using marijuana 

regularly. In 2009, those rates dropped to about 70 percent of 8th graders, 60 percent of 10th

graders, and 55 percent of 12th graders.20

Treatment

Long-term marijuana users who are trying to stop using the drug report symptoms such as 

irritability, sleeplessness, decreased appetite, anxiety, and drug craving, all of which make it 

difficult to quit.21 In 2008, nearly 68 percent of primary treatment admissions for youth 

between the ages of 12 and 17 were for marijuana.

22 Although there are no medications for 

treating marijuana abuse, behavioral interventions, including cognitive behavioral therapy and 

motivational incentives (i.e., providing vouchers for goods or services to patients who abstain 

from drug use), have shown efficacy in treating marijuana dependence.23

A Threat to the Environment

Outdoor marijuana cultivation sites are becoming increasingly common. These “grows” often 

result in the destruction of natural habitat from diesel spills, pesticide runoff, and trash from 
ONDCP seeks to foster healthy individuals and safe communities by effectively 

leading the Nation’s effort to reduce drug use and its consequences.

October 2010 

cultivators.24 National parks and other public lands in the United States are used for cannabis 

cultivation operations, primarily by Mexican criminal groups. Data from the Department of 

Agriculture Forest Service and the Department of the Interior indicate that more than 4 million 

marijuana plants were eradicated from U.S. public lands in 2008 alone.

25

Notes 

 

1

University of Michigan, Institute for Social Research. “The Monitoring the Future Study: 2009 Results.”

http://monitoringthefuture.org/pubs/monographs/overview2009.pdf

2

 SAMHSA, 2009 National Survey on Drug Use and Health (September 2010). 

3

 SAMHSA, 2009 National Survey on Drug Use and Health (September 2010). 

4

SAMHSA, 2009 National Survey on Drug Use and Health (September 2010).

5

National Center for Natural Products Research (NCNPR), Research Institute of Pharmaceutical Sciences. Quarterly Report, Potency Monitoring 

Project, Report 107, September 16, 2009 thru December 15, 2009. University, MS: NCNPR, Research Institute of Pharmaceutical Sciences, School 

of Pharmacy, University of Mississippi (January 12, 2010).

6

 Drug Enforcement Administration, “Schedules of Controlled Substances.”

http://www.justice.gov/dea/pubs/abuse/1-csa.htm

7

 National Center for Natural Products Research (NCNPR), Research Institute of Pharmaceutical Sciences. Quarterly Report, Potency Monitoring 

Project, Report 107, September 16, 2009 thru December 15, 2009. University, MS: NCNPR, Research Institute of Pharmaceutical Sciences, School 

of Pharmacy, University of Mississippi (January 12, 2010). 

8

 Herkenham M, Lynn A, Little MD, et al. Cannabinoid receptor localization in the brain. Proc Natl Acad Sci, USA 

87(5):1932–1936, 1990. 

9

 Pope HG, Gruber AJ, Hudson JI, Huestis MA, Yurgelun-Todd D. Neuropsychological performance in long-term

cannabis users. Arch Gen Psychiatry 58(10):909–915, 2001. 

10 Moore TH, Zammit S, Lingford-Hughes A, et al. Cannabis use and risk of psychotic or affective mental health 

outcomes: A systematic review. Lancet 370(9584):319–328, 2007. 

11 Hoffman, D.; Brunnemann, K.D.; Gori, G.B.; and Wynder, E.E.L. On the carcinogenicity of marijuana smoke. In: V.C. Runeckles, ed., Recent 

Advances in Phytochemistry. New York: Plenum, 1975. 

12 Office of National Drug Control Policy, “Drug Free Communities Program.”

http://www.ondcp.gov/dfc/overview.html

13 Substance Abuse and Mental Health Services Administration. “Screening, Brief Intervention, and Referral to Treatment” (2009). 

http://sbirt.samhsa.gov/about.htm

14 Substance Abuse and Mental Health Services Administration. “Screening, Brief Intervention, and Referral to Treatment” (2009).

http://sbirt.samhsa.gov/about.htm

15 Substance Abuse and Mental Health Services Administration, “Strategic Prevention Framework State Incentive Grant.”

http://prevention.samhsa.gov/grants/sig.aspx

16 Volkow, N. Research Report: Marijuana Abuse, National Institute on Drug Abuse. 

http://www.drugabuse.gov/ResearchReports/Marijuana/default.html 

17 SAMHSA, 2009 National Survey on Drug Use and Health (September 2010). 

18 University of Michigan, Institute for Social Research. “The Monitoring the Future Study: 2009 Results.” 

http://monitoringthefuture.org/pubs/monographs/overview2009.pdf

19 SAMHSA, 2009 National Survey on Drug Use and Health (September 2010).

20 University of Michigan, Institute for Social Research. “The Monitoring the Future Study: 2009 Results.”

http://monitoringthefuture.org/pubs/monographs/overview2009.pdf 

21 Budney AJ, Vandrey RG, Hughes JR, Thostenson JD, Bursac Z. Comparison of cannabis and tobacco withdrawal: 

Severity and contribution to relapse. J Subst Abuse Treat 35(4):362–368, 2008. 

22 Substance Abuse and Mental Health Services Administration, “Highlights for the 2008 Treatment Episode Data Set.” 

http://www.oas.samhsa.gov/TEDS2k7highlights/TEDSHighl2k7Tbl3.htm

23 Stephens, R.S.; Roffman R.A.; and Curtin, L. Comparison of extended versus brief treatments for marijuana use. J Consult Clin Psychol

68(5):898-908, 2000. 

Budney, A.J.; Higgins, S.T.; Radonovich, K.J.; and Novy PL. Adding voucher-based incentives to coping skills and motivational enhancement 

improves outcomes during treatment for marijuana dependence. J Consult Clin Psychol 68(6):1051-1061, 2000.

24 National Drug Intelligence Center. “Impact of Drugs on Society” (2010). 

http://www.justice.gov/ndic/pubs38/38661/drugImpact.htm

25 National Drug Intelligence Center, Domestic Cannabis Cultivation Assessment, 2009. 

http://www.justice.gov/ndic/pubs37/37035/public.htm#Top