Marijuana is the dried flowers, leaves and stems of the Cannabis sativa plant. The main active ingredient in marijuana is THC (delta 9 tetrhydrocannabinol). Marijuana can range from 1% THC to 8%. Hashish can be 7% to 14% THC and hash oil is up to 50% THC. THC is a fat soluble substance and can remain in the lungs and brain tissue for up to 3 weeks. There are over 200 nicknames for marijuana, including pot, herb, mary jane and chronic.
Marijuana is usually smoked, using a pipe, a bong or by rolling a joint. Blunts are cigars that are emptied of tobacco and refilled with marijuana, sometimes in combination with other drugs. It can also be eaten in food, for example, by baking it in brownies. Eating marijuana will delay the onset of the effects, but they will last longer.
Smoking marijuana can relax a person and elevate their mood. This can be followed by drowsiness and sedation. Other effects include heightened sensory awareness, euphoria, altered perceptions and feeling hungry ("the munchies"). High concentrations of THC may produce a more hallucinogenic response.
Discomforts associated with smoking marijuana include dry mouth, dry eyes, increased heart rate and visible signs of intoxication such as bloodshot eyes and puffy eyelids. Other problems include:
- Impaired short-term memory
- Difficulty thinking and problem solving
- Anxiety attacks or feelings of paranoia
- Impaired muscle coordination and judgment
- Increased susceptibility to infections
- Dangerous impairment of driving skills. Studies show that it impairs braking time, attention to traffic signals and other driving behaviors. This impairment can last 12 to 24 hours due to accumulation of marijuana in fatty tissue.
- Cardiac problems for people with heart disease or high blood pressure, because marijuana increases the heart rate
It is virtually impossible to overdose from marijuana, which sets it apart from most drugs.
Memory and learning
Research shows that regular marijuana use compromises the ability to learn and to remember information by impairing the ability to focus, sustain, and shift attention. One study also found that long-term use reduces the ability to organize and integrate complex information.
In addition, marijuana impairs short-term memory and decreases motivation to accomplish tasks, even after the high is over. In one study, even small doses impaired the ability to recall words from a list seen 20 minutes earlier.
Marijuana use is associated with increased prevalence of depression, schizophrenia and psychosis. It remains unclear whether marijuana triggers the onset of these illnesses only in vulnerable people or whether it can cause them in people who would not have developed them otherwise.
Long-term marijuana use suppresses the production of hormones that help regulate the reproductive system. For men, this can cause decreased sperm counts and sperm motility and heavy users can experience erectile dysfunction. Women may experience irregular periods from heavy marijuana use. These problems would most likely result in a decreased ability to conceive but not lead to complete infertility.
No one would argue that marijuana is as addictive as alcohol or cocaine. However, it's wrong to say that it is not at all addictive. More and more studies are finding that marijuana has addictive properties. Both animal and human studies show physical and psychological withdrawal symptoms from marijuana, including irritability, restlessness, insomnia, nausea and intense dreams. Tolerance to marijuana also builds up rapidly. Heavy users need 8 times higher doses to get the same effects as infrequent users.
For a small percentage of people who use it, marijuana can be highly addictive. It is estimated that 10% to 14% of users will become heavily dependent. In 2006 marijuana was responsible for 16% of all admissions to treatment facilities in the U.S. Because the consequences of marijuana use can be subtle and insidious, it is more difficult to recognize signs of addiction. Cultural and societal beliefs that marijuana cannot be addictive make it less likely for people to seek help or to get support for quitting.
Some warning signs are:
- More frequent use
- Needing more and more to get the same effect
- Spending time thinking about using marijuana
- Spending more money than you have on it
- Missing class or failing to finish assignments because of marijuana
- Making new friends who do it and neglecting old friends who don't
- Finding it's hard to be happy without it
Because THC is fat soluble and remains in the body for up to 3 weeks, it's important to remember that withdrawal symptoms might not be felt immediately. If you find that you can't stop using marijuana, then remember, there's help on campus.
Yes, marijuana is illegal and its possession, use, and sale carry prison sentences and fines and disciplinary consequences at Brown. See the Brown University Policy on Drugs in the Student Handbook.
Marijuana's ability to enhance appetite has led to its medical use to reduce the physical wasting caused by AIDS and to reduce nausea for chemotherapy patients. Over 10 states have laws that allow patients to use medical marijuana despite the prohibition by federal law. For more information on state and federal laws, go to the Marijuana Policy Project.
If you are concerned about a friend's drug or alcohol use, this page contains information about different ways to help them.
If you or a friend are having trouble with drugs or alcohol, or just have questions, there is help available.
The Good Drugs Guide
This British harm-reduction web site provides extensive information on marijuana, including the basics, dangers, debates over legalization, and links.
Busted: America’s War on Marijuana
This PBS Front-line program goes behind the scenes of America's marijuana industry, examining the production, sale and effort to eradicate the use of this drug. Topics include the criminal justice system, marijuana's treatment in popular culture and efforts to prevent use by teenagers. Online features include interviews, video excerpts and health effects of marijuana.
MA uses the basic 12-step recovery program for people who are addicted to marijuana. Online groups are available, as well as publications, frequently asked questions and 12 questions to determine if marijuana is a problem in your life. The literature section has stories by teens, help for loved ones of marijuana addicts, and the dangers of cross addiction.
e-toke is a free, anonymous assessment tool that provides individualized feedback on the role marijuana is playing in your life. You can also see how your use compares with other college students. If you would like to talk to someone about your use, you can call Health Education at 863-2794 for an appointment or click here for other resources.
MEDLINEplus Health Information
This search page will give you links to marijuana facts, prevention and screening, research, treatment and statistics. Fact sheets available in Spanish.
National Institute on Drug Abuse
This site has statistics, drug information and recent research reports on marijuana.
Online Drug Screening
This confidential and anonymous survey gives you feedback about the likely risks of your alcohol and drug use.
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