Marijuana

  • Medical Author:
    Roxanne Dryden-Edwards, MD

    Dr. Roxanne Dryden-Edwards is an adult, child, and adolescent psychiatrist. She is a former Chair of the Committee on Developmental Disabilities for the American Psychiatric Association, Assistant Professor of Psychiatry at Johns Hopkins Hospital in Baltimore, Maryland, and Medical Director of the National Center for Children and Families in Bethesda, Maryland.

  • Medical Editor: Melissa Conrad Stöppler, MD
    Melissa Conrad Stöppler, MD

    Melissa Conrad Stöppler, MD

    Melissa Conrad Stöppler, MD, is a U.S. board-certified Anatomic Pathologist with subspecialty training in the fields of Experimental and Molecular Pathology. Dr. Stöppler's educational background includes a BA with Highest Distinction from the University of Virginia and an MD from the University of North Carolina. She completed residency training in Anatomic Pathology at Georgetown University followed by subspecialty fellowship training in molecular diagnostics and experimental pathology.

Prescription Drug Abuse Statistics

Marijuana facts

  • Marijuana's (scientific name is Cannabis sativa) leaves, seeds, stems and/or roots are consumed by marijuana users for the purpose of feeling intoxicated.
  • THC, or tetrahydrocannibinol, is one of the hundreds of compounds within marijuana that has major intoxicating effects.
  • Marijuana that is consumed for medical purposes, like for patients with nausea or poor appetite associated with AIDS or cancer treatment, is legal in a few states of the United States.
  • Possession of marijuana, regardless of its purpose, is illegal in most jurisdictions.
  • Marijuana is the most commonly abused illegal substance worldwide.
  • While the number of people who use marijuana at any one time does not seem to have recently increased, the number of people who have a marijuana-related disorder has risen significantly. This is more or less true depending on age and ethnic group.
  • Medical marijuana, also called marinol (Dronabinol), is a synthetic form of marijuana.
  • There are many ways of referring to marijuana itself, as well as for how it is smoked.
  • The history of marijuana goes back for thousands of years. It was only made illegal in many countries during the 20th century.
  • The use of medical marijuana is currently legal in 20 U.S. states and the District of Columbia. In those jurisdictions, people for whom medical marijuana has been specifically recommended by a physician must carry a (medical) marijuana card that indicates their use of the substance for a clear medical purpose.
  • Attempts to completely legalize the use of marijuana, whether for medicinal purposes or not, remain strongly contested in most jurisdictions.
  • There are a variety of marijuana types, also called strains.
  • Numerous research studies show that marijuana is indeed an addictive substance. The symptoms of addiction to marijuana are similar to those of any other addictive substance.
  • The symptoms of marijuana withdrawal are similar to those of other drugs and include irritability, anger, depression, insomnia, drug craving, and decreased appetite.
  • The negative physical, psychological, and social effects of marijuana are numerous.
  • While most individuals with marijuana abuse or dependence are treated on an outpatient basis, admission to both outpatient and inpatient treatment programs for marijuana addiction has increased over the years.
  • Behavioral and family based treatments have been found to be effective for marijuana abuse and addiction.
  • There is as yet no medication that has yet been shown to be a clearly effective treatment of marijuana-use disorders.

Quick GuideSlideshow: Medical Marijuana

Slideshow: Medical Marijuana

What is marijuana, and how is it abused?

Marijuana is a plant whose scientific name is Cannabis sativa. Its leaves, seeds, stems, and/or roots are consumed by marijuana users for the purpose of feeling intoxicated ("high"). Although the plant contains hundreds of compounds, the one that has major intoxicating effects is called tetrahydrocannibinol (THC). Although medical marijuana is legal in a few states of the United States, it is one of many illegal drugs in most jurisdictions. Specifically, laws in most states deem it illegal to engage in possession of marijuana, either for the purpose of your own use or for the purpose of distributing it to others.

Marijuana is the most commonly abused illegal substance worldwide. While the number of people who use marijuana at any one time does not seem to have increased in the past decade, the number of people who have a marijuana-related disorder has increased significantly. This seems to be particularly true for elderly individuals as well as for young Hispanic and African-American adults. In teens, boys remain more likely than girls to smoke or otherwise use marijuana. Native-American adolescents seem to be the ethnic group most vulnerable to engage in recent marijuana use, and Asian adolescents tend to be the least likely.

What is medical marijuana? How is medical marijuana prescribed?

Medical marijuana, also called marinol (Dronabinol), is a synthetic form of marijuana. It comes in 2.5 mg, 5 mg, and 10 mg capsules and is used for the treatment of poor appetite and food intake (anorexia) with weight loss in people with acquired immune deficiency syndrome (AIDS) and for the nausea and vomiting due to cancer chemotherapy in individuals who have not responded adequately to usual treatments for those symptoms. When used for appetite stimulation, marinol is usually dosed at 2.5 mg once or twice per day before lunch, dinner, and/or bedtime. When it is being prescribed to quell nausea, it is usually prescribed at 5 mg, one to three hours before a chemotherapy treatment and every two to four hours after chemotherapy, up to six doses per day.

The most common physical side effects of marinol include asthenia (lack of energy), stomach upset, nausea, vomiting, racing heart rate, facial flushing, and dizziness. The most common psychological side effects of marinol include anxiety, sleepiness, confusion, hallucinations, and paranoia. This medication should therefore be used with caution in persons who have a mental-health diagnosis, particularly depression, mood swings, schizophrenia, or substance abuse. When prescribed for those people, the individual is usually under the care of a psychiatrist.

What are other names for marijuana?

There are many, many ways of referring to marijuana. The technical term for marijuana is cannabis. Some terms like pot, hemp, herb, reefer, ganja, and weed refer to the substance itself. A higher potency form of marijuana is often called hashish or hash. Other words like joints, blunts, backwoods, buds, or bongs refer to the way that marijuana is smoked. Marijuana is also often smoked in pipes or baked in food, like brownies.

What is the history and different types of marijuana?

The history of marijuana goes back for thousands of years. It was only made illegal in many countries during the 20th century. In the past 20 years in the United States, the legalization pros and cons of medical marijuana have been intensely debated as it has become legal to use it in 20 states and the District of Columbia. In those jurisdictions, people for whom medical marijuana has been specifically recommended by a physician must carry a (medical) marijuana card that indicates their use of the substance for a clear medical purpose. Individuals who do not carry such a card risk prosecution for marijuana possession. Different states that allow for legal use of marijuana have different guidelines for the legality of possessing and using medical marijuana. For example, at least one bans home cultivation, and there are regulations concerning the operations of dispensaries in some states.

Federal laws continue to deem marijuana possession, as well as its distribution, as illegal, whether it is used for medicinal purposes or not. While the prosecution rates of individuals who carry small amounts of the substance along with a medical marijuana card tend to be low, dispensaries in states that have legalized medical marijuana remain criminalized and are therefore often raided by law-enforcement agencies.

Attempts to completely legalize the use of marijuana, whether for medicinal purposes or not, remain strongly contested in most jurisdictions. For example, in 2010, Proposition 19, a measure that would have completely legalized possession and growing marijuana then taxed and regulated its use was defeated in the state of California. However, California already reduced legal sanctions for possessing small amounts of marijuana to the level comparable to the penalty for speeding on a freeway.

There are a variety of marijuana types, also called strains. Strains tend to be based on leaf color as indicated in pictures, as well as the strains' potency and medical purpose. Medical strains of marijuana are specifically grown for a particular health benefit, like pain management or reduction of nausea. Some states place restrictions on the strains of marijuana that may be legally used and sold. Marijuana dispensaries often sell hydroponic marijuana seeds through mail order, which can be grown in nutrient solution, with or without soil.

Quick GuideSlideshow: Medical Marijuana

Slideshow: Medical Marijuana

Is marijuana addictive?

Numerous research studies show that marijuana is indeed an addictive substance. The rate of addiction to marijuana has increased for all age groups. Teens are using the drug at younger ages. About one out of every six adolescents who use marijuana develop addiction to it, and half the people who receive treatment for marijuana use are under the age of 25. While the frequency of use seems to have remained the same over the past several years, adults are becoming dependent on marijuana more often. Theories about potential reasons for that increase include increased access to marijuana that is of higher potency, as well as a lower age at which many individuals first use this drug.

The symptoms of addiction to marijuana are similar to those of any other addictive substance. As with any other drug, in order to qualify for the diagnosis of marijuana addiction, the individual must suffer from a negative pattern of use of this drug, which results in significant problems or suffering, with at least three of the following symptoms occurring at the same time in the same one year period:

  • Tolerance (decreased effects of marijuana over time or needing to increase the amount used to achieve the desired effect)
  • Withdrawal (characteristic symptoms that occur when the individual abstains from using marijuana for some days)
  • Often taking marijuana in larger amounts or over a longer period of time than planned
  • Persistent desire to use marijuana or trouble decreasing or controlling its use
  • Spending significant time either obtaining marijuana (for example, buying, growing), using it, or recovering from its effects
  • Significant social, educational, occupational, or leisure activities are either abandoned or significantly decreased as a result of marijuana's use
  • Marijuana use continues despite being aware of or experiencing persistent or repeated physical or psychological problems as a result of its use

The symptoms of marijuana withdrawal are similar to those of other drugs, especially tobacco. Those symptoms usually start one to two days after last using marijuana and include irritability, anger, depression, insomnia, drug craving, and decreased appetite. These symptoms tend to interfere with the individual's attempts to stop using marijuana and can motivate the use of both marijuana and other drugs for relief. The symptoms of withdrawal tend to peak within four to six days and last from one to three weeks.

What are the psychological and social effects of abusing marijuana?

The bad effects of marijuana are numerous. For example, it can impair thinking, as in learning, and memory for several days after each time it is used. That risk seems to be even higher for people who score lower on IQ tests compared to those who score higher.

The social effects of smoking marijuana can be quite detrimental as well. Adolescents who use the substance are at higher risk of pregnancy, dropping out of school, delinquency, legal problems, and achieving less educationally and occupationally. Individuals who become dependent on marijuana tend to be less motivated, less happy, or satisfied with their life. They are also at risk for depression and for using larger amounts of alcohol and other drugs.

What are the physical effects of abusing marijuana?

In terms of how long marijuana tends to stay in your system, it can be detected on drug tests for about two weeks. Like many other chemicals that are ingested, marijuana can affect your body in many ways. It seems to be associated with an increased occurrence of certain cancers. It may also increase the risk of sexual dysfunction; statistics indicate that men who smoke or otherwise consume marijuana regularly are at higher risk of either having premature ejaculation or trouble reaching orgasm. Men and women who use this substance on a regular basis seem to have more sexual partners and to be more at risk for contracting sexually transmitted diseases compared to those who do not use marijuana.

Marijuana's effects on the body and brain of a developing fetus seem to be clearly negative. Exposure to this substance before birth (prenatally) is associated with negative effects on fetal growth and body weight, as well as on the impulse control, focusing ability, learning, memory, and decision making in the child who was exposed to marijuana before birth. These negative effects by no means only affect babies who are exposed to marijuana before birth (in utero). Marijuana tends to negatively affect learning, judgment, and muscle skills in people who use marijuana by their own volition.

Quick GuideSlideshow: Medical Marijuana

Slideshow: Medical Marijuana

What are the treatments for marijuana abuse and addiction?

Most individuals with marijuana abuse or dependence are treated on an outpatient basis. Admission to outpatient and inpatient treatment programs for marijuana addiction has increased over the years to the point that the addiction to this substance is nearly as high as dependence on other illegal drugs, like cocaine or heroin.

Behavioral treatments, like motivational enhancement therapy (MET), cognitive-behavioral therapy (CBT), and contingency management (CM), as well as family based treatments have been found to be effective treatments for marijuana abuse and addiction. MET is designed to lessen the resistance a person who abuses marijuana may have to abstaining from using it. This intervention is also designed to motivate the individual to change. CBT teaches people who abuse marijuana skills to help them stop using the drug and to ways to avoid or manage other problems that might prevent them from marijuana use recovery. CM usually provides marijuana users with vouchers of increasing value as a reward for repeatedly testing negative for (the absence of) drugs over time. Those vouchers are then exchanged for positive items or services that promote the person's participation in more positive (pro-social) activities, like securing employment or advancing their education or health.

In addition to the individual therapies just described, adolescents who abuse or are addicted to marijuana are often treated using one or more family therapies. These include multidimensional therapy, multisystemic therapy, family support network intervention, and brief strategic family therapy. Each of these interventions uses techniques that are designed to enhance the skills of the addicted individual and his or her family members as a way of discouraging marijuana use.

Although there is no medication that has yet been shown to be a clearly effective treatment of marijuana-use disorders, research shows that antidepressant medications like nefazodone (Serzone) and fluoxetine (Prozac) may help some individuals manage marijuana withdrawal and to avoid relapse, respectively. Oral THC (Dronabinol) may also help alleviate symptoms of marijuana withdrawal. Successful psychotherapeutic approaches to treatment of marijuana abuse or addiction include motivational approaches with coping skills development.

Can marijuana abuse and addiction be prevented?

In order to prevent marijuana use, abuse, and addiction, an understanding of the risk factors for those issues is essential. In teens, availability of marijuana in their environment, as well as a tendency to engage in negative behaviors (deviancy) increase the likelihood of marijuana use. For some adolescents, using legal substances like alcohol and tobacco can be gateway drugs for marijuana use, in that the use of those substances increases the likelihood that the teen will use marijuana.

What is the prognosis of marijuana abuse and addiction?

While many people with a marijuana-use disorder successfully stop using it with outpatient psychotherapy that provides motivation and teaches coping skills, the relapse rate is quite high. However, when treatment is provided frequently, that statistic improves. Individuals who begin smoking marijuana before 17 years of age seem to be more than three times more likely to attempt suicide than those who either never use the substance or do so after the age of 17. That risk goes the other way as well, in that people who develop depression or have thoughts of suicide before the age of 17 seem to be at a much higher risk of developing an addiction to marijuana. People who are vulnerable to developing psychosis (for example, having hallucinations like seeing things or hearing voices that aren't there; or delusions, like unfounded beliefs that others are trying to harm him or her) may be more likely to do so if marijuana is used, even on a medicinal basis. Marijuana abuse or addiction is also associated with a much higher risk of developing a dependence on other drugs.

Where can people find more information about marijuana abuse and addiction?

Medically reviewed by Marina Katz, MD; American Board of Psychiatry & Neurology

REFERENCES:

American Psychiatric Association. Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition-Treatment Revision 2001.

American Psychiatric Association. Practice guideline for the treatment of patients with substance use disorders, second edition. In, American Psychiatric Association Practice Guidelines: Treatment of Patients With Substance Use Disorders 2006 May.

Budney AJ, Roffman R, Stephens RS, Walker D. Marijuana dependence and its treatment. Addiction Science in Clinical Practice 2007 December; 4(1): 4-16.

Callaway E. Regular marijuana usage robs men of sexual highs. Journal of Sexual Medicine 2009 August; 16: 2.

Elkashef A, Vocci F, Huestis M, et al. Marijuana neurobiology and treatment. Substance Abuse 2008; 29(3): 17-29.

Looby A, Earleywine M. Negative consequences associated with dependence in daily cannabis users. Substance Abuse Treatment and Prevention Policy 2007; 2: 3.

Merriam Webster's Dictionary 2011. www.merriam-webster.com.

National Institute on Drug Abuse. Gender and ethnic patterns in drug use among high school seniors 2003 August; 18(2).

National Institute on Drug Abuse. Teen marijuana use increases, especially among eighth-graders 2010 December.

New York Times Company. Marijuana and medical marijuana. The New York Times 2011 August 6.

PDR.net. Physicians' Desk Reference. 2011. http://www.pdr.net.

Pierre JM. Psychosis associated with medicinal marijuana: risk vs. benefits of medicinal cannabis use. American Journal of Psychiatry 2010 May; 167: 598-599.

Tarter RE, Vanyukov M, Kirisci L, Reynolds M, Clark DB. Predictors of marijuana use in adolescents before and after licit drug use: examination of the gateway hypothesis. American Journal of Psychiatry 2006 December; 163: 2134-2140.

Williams JS. Cognitive Deficits in marijuana smokers persist after use stops. National Institute on Drug Abuse 2003 December;18(5).

Zhang ZF, Morgenstern H, Spitz MR, et al. Marijuana use and increased risk of squamous cell carcinoma of the head and neck. Cancer Epidemiological Biomarkers Preview 1999 December; 8(12): 1071-1078.

Zickler P. Marijuana-related disorders, but not prevalence of use, rise over past decade. National Institute on Drug Abuse 2005 May; 19(6).

Zickler P. Twin study links marijuana abuse, suicide and depression. National Institute on Drug Abuse 2005 August; 20(2).

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Reviewed on 11/19/2015
References
Medically reviewed by Marina Katz, MD; American Board of Psychiatry & Neurology

REFERENCES:

American Psychiatric Association. Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition-Treatment Revision 2001.

American Psychiatric Association. Practice guideline for the treatment of patients with substance use disorders, second edition. In, American Psychiatric Association Practice Guidelines: Treatment of Patients With Substance Use Disorders 2006 May.

Budney AJ, Roffman R, Stephens RS, Walker D. Marijuana dependence and its treatment. Addiction Science in Clinical Practice 2007 December; 4(1): 4-16.

Callaway E. Regular marijuana usage robs men of sexual highs. Journal of Sexual Medicine 2009 August; 16: 2.

Elkashef A, Vocci F, Huestis M, et al. Marijuana neurobiology and treatment. Substance Abuse 2008; 29(3): 17-29.

Looby A, Earleywine M. Negative consequences associated with dependence in daily cannabis users. Substance Abuse Treatment and Prevention Policy 2007; 2: 3.

Merriam Webster's Dictionary 2011. www.merriam-webster.com.

National Institute on Drug Abuse. Gender and ethnic patterns in drug use among high school seniors 2003 August; 18(2).

National Institute on Drug Abuse. Teen marijuana use increases, especially among eighth-graders 2010 December.

New York Times Company. Marijuana and medical marijuana. The New York Times 2011 August 6.

PDR.net. Physicians' Desk Reference. 2011. http://www.pdr.net.

Pierre JM. Psychosis associated with medicinal marijuana: risk vs. benefits of medicinal cannabis use. American Journal of Psychiatry 2010 May; 167: 598-599.

Tarter RE, Vanyukov M, Kirisci L, Reynolds M, Clark DB. Predictors of marijuana use in adolescents before and after licit drug use: examination of the gateway hypothesis. American Journal of Psychiatry 2006 December; 163: 2134-2140.

Williams JS. Cognitive Deficits in marijuana smokers persist after use stops. National Institute on Drug Abuse 2003 December;18(5).

Zhang ZF, Morgenstern H, Spitz MR, et al. Marijuana use and increased risk of squamous cell carcinoma of the head and neck. Cancer Epidemiological Biomarkers Preview 1999 December; 8(12): 1071-1078.

Zickler P. Marijuana-related disorders, but not prevalence of use, rise over past decade. National Institute on Drug Abuse 2005 May; 19(6).

Zickler P. Twin study links marijuana abuse, suicide and depression. National Institute on Drug Abuse 2005 August; 20(2).

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