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Substance use - marijuana

Substance abuse - marijuana; Drug abuse - marijuana; Drug use - marijuana; Cannabis; Grass; Hashish; Mary Jane; Pot; Weed

Marijuana comes from a plant called hemp. Its scientific name is Cannabis sativa. The main, active ingredient in marijuana is THC (short for delta-9-tetrahydrocannabinol). This ingredient is found in the leaves and flowering parts of the marijuana plant. Hashish is a substance taken from the tops of female marijuana plants. It contains the highest amount of THC.

Marijuana is called by many other names, including cannabis, grass, hashish, joint, Mary Jane, pot, reefer, weed.

Some states in the United States permit marijuana to be used legally to treat certain medical problems. Other states have also legalized its recreational use.

This article is on the recreational use of marijuana, which may lead to abuse.

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Marijuana's Effects on Your Brain

The THC in marijuana acts on your brain (central nervous system). THC causes brain cells to release dopamine. Dopamine is a chemical that is involved with mood and thinking. It is also called the feel-good brain chemical. Using marijuana may cause pleasurable effects such as:

How fast you feel the effects of marijuana depends on how you use it:

Harmful Effects of Marijuana

Marijuana can also have unpleasant effects:

Marijuana's other health effects include:

Marijuana can be Addictive

Some people who use marijuana get addicted to it. This means their body and mind are dependent on marijuana. They are not able to control their use of it and they need it to get through daily life.

Addiction can lead to tolerance. Tolerance means you need more and more marijuana to get the same high feeling. And if you try to stop using, your mind and body may have reactions. These are called withdrawal symptoms, and may include:

Treatment Options

Treatment begins with recognizing there is a problem. Once you decide you want to do something about your marijuana use, the next step is getting help and support.

Treatment programs use behavior change techniques through counseling (talk therapy). Some programs use 12-step meetings to help people learn how not to relapse. The goal is to help you understand your behaviors and why you use marijuana. Involving family and friends during counseling can help support you and keep you from going back to using (relapsing).

If you have severe withdrawal symptoms, you may need to stay at a residential treatment program. There, your health and safety can be monitored as you recover.

At this time, there is no medicine that can help reduce the use of marijuana by blocking its effects. But, scientists are researching such medicines.

Your Ongoing Recovery

As you recover, focus on the following to help prevent relapse:

Resources

Resources that may help you on your road to recovery include:

Your workplace employee assistance program (EAP) is also a good resource.

When to Call the Doctor

Call for an appointment with your health care provider if you or someone you know is addicted to marijuana and needs help stopping. Also call if you are having withdrawal symptoms that concern you.

References

Kowalchuk A, Reed BC. Substance use disorders. In: Rakel RE, Rakel DP, eds. Textbook of Family Medicine. 9th ed. Philadelphia, PA: Elsevier; 2016:chap 50.

National Academies of Sciences, Engineering, and Medicine; Health and Medicine Division; Board on Population Health and Public Health Practice; Committee on the Health Effects of Marijuana: An Evidence Review and Research Agenda. The Health Effects of Cannabis and Cannabinoids: The Current State of Evidence and Recommendations for Research. Washington, DC: National Academies Press; 2017.

National Institute on Drug Abuse website. Marijuana. www.drugabuse.gov/publications/research-reports/marijuana/what-marijuana. Updated July 2020. Accessed August 17, 2022.

Weiss RD. Drugs of abuse. In: Goldman L, Schafer AI, eds. Goldman-Cecil Medicine. 26th ed. Philadelphia, PA: Elsevier; 2020:chap 31.

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Review Date: 4/30/2022  

Reviewed By: Fred K. Berger, MD, addiction and forensic psychiatrist, Scripps Memorial Hospital, La Jolla, CA. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.

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