What is marijuana?

Marijuana is an illegal drug that comes from dried flowers and leaves of the hemp plant. It can be smoked, taken by the mouth, or put into foods. When taken, marijuana alters a person's mood. Its psychological effects include:

  • Intense sensations and a heightened awareness of music, food or surroundings
  • A feeling of contentment or well-being
  • Increased appetite

Larger doses of marijuana can produce:

  • Confusion
  • Hallucinations
  • Paranoia

Marijuana available today is more than 20 times as potent as what was available in the early 1960s.

What's so bad about marijuana?

Marijuana is risky for many reasons. Consider these facts:

  • It makes it more difficult for the body to fight illnesses.
  • When smoked, marijuana contains more than 2,000 chemicals that can stay in your body up to a month.
  • Marijuana can harm the heart, lungs, brain, and sex organs.
  • Marijuana contains more cancer-causing agents than cigarettes.

Marijuana use can lead to:

  • Asthma
  • Memory loss
  • Panic attacks
  • Lung damage
  • Brain damage
  • Slowed reaction time
  • Change in sex drive
  • Death due to impaired driving
  • False beliefs
  • Unfounded fear or distrust
  • Decreased immunity to illnesses

People who use marijuana often:

  • Lack energy and motivation.
  • Lose interest in activities, work, and school.
  • Have difficulty concentrating and learning.

When should I seek help for marijuana use?

If you can answer "yes" to even one of these questions, it is time to seek help:

  • Do you often wonder when you can smoke again?
  • Do you worry if you can't get marijuana?
  • Is smoking marijuana creating problems in your job, school, or relationships?
  • Do you spend more and more money on pot?
  • Have you been stopped for driving while high?

Can a person become addicted to marijuana?

Yes. A person who uses marijuana heavily might find that he or she needs more and more of the drug to obtain the desired effect. This condition happens when the body begins to adjust to marijuana. The user may spend more time and money on his or her drug habit. As an addict, he or she might:

  • Behave less responsibly.
  • Withdraw from family and friends.
  • Be overly focused on getting the drug at the expense of other activities.

Unlike drugs such as heroin and cocaine, marijuana does not produce strong physical withdrawal symptoms. What's most important to remember is that any time drug or alcohol use continues to affect your life in a negative way, it's time to seek help.

How can I help someone who is abusing marijuana?

Although it might be obvious to you that someone you care about needs help, people with drug problems often do not believe they have a problem. Arguing or trying to push someone to stop using or taking drugs rarely works. There are ways that you can help the person realize that he or she needs help.

  • Don't attempt to "shame" the person out of drug use. Feelings of guilt or shame are often a cause of drug use.
  • Don't confront a person who is high or drunk. Let him or her know how you feel when he or she is not using.
  • Don't lend money for drugs.
  • Encourage the user to seek help.
  • Get help for yourself, if you need it.

How is marijuana abuse treated?

Counseling is the main form of treatment. The goal of counseling is to help the person confront emotional issues that lead to marijuana use and to learn ways to abstain from marijuana use.

Recovery programs vary in length and can take place in residential treatment centers or outpatient settings.

Where can I seek help?

National Institute on Drug Abuse. https://www.drugabuse.gov/drugs-abuse/alcohol

U.S. Department of Health & Human Services. SAMHSA: Substance Abuse and Mental Health Services Association

Last reviewed by a Cleveland Clinic medical professional on 07/29/2014.


  • National Council on Alcoholism and Drug Dependence, Inc. Marijuana Accessed 8/28/2014.
  • National Institute on Drug Abuse. Marijuana Accessed 8/28/2014.
  • Partnership for Drug-Free Kids Accessed 8/28/2014.
  • O'Brien CP. Chapter 24. Drug Addiction. In: Brunton LL, Chabner BA, Knollmann BC. eds. Goodman & Gilman's The Pharmacological Basis of Therapeutics, 12e. New York, NY: McGraw-Hill; 2011. library.ccf.org Accessed 8/28/2014.

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