- Marijuana can be addictive, with some frequent, heavy users developing tolerance and experiencing withdrawal symptoms like irritability and sleeplessness when trying to quit. - Long-term marijuana abuse can lead to addiction and negatively impact social functioning and intellectual ability due to effects on learning and memory that persist after the drug wears off. - While most teens do not use marijuana, current rates of teen use are around one in six for 10th graders and fewer than one in five for high school seniors.

1. Can People Become Addicted to Marijuana? Yes. While not everyone who uses marijuana becomes addicted, when a user begins to seek out and take the drug compulsively, that person is said to be dependent or addicted to the drug. In 1995, 165,000 people entering drug treatment programs reported marijuana as their primary drug of abuse, showing they need help to stop using the drug. According to one study, marijuana use by teenagers who have prior serious antisocial problems can quickly lead to dependence on the drug. Some frequent, heavy users of marijuana develop a tolerance for it. "Tolerance" means that the user needs larger doses of the drug to get the same desired results that he or she used to get from smaller amounts. Teens who have received treatment for marijuana use have reported having withdrawal symptoms.

2. Marijuana and Addiction Long-term marijuana abuse can lead to addiction; that is, compulsive drug seeking and abuse despite its known harmful effects upon social functioning in the context of family, school, work, and recreational activities. Long-term marijuana abusers trying to quit report irritability, sleeplessness, decreased appetite, anxiety, and drug craving, all of which make it difficult to quit. These withdrawal symptoms begin within about 1 day following abstinence, peak at 2-3 days, and subside within 1 or 2 weeks following drug cessation.

3. The Effects of Marijuana Use THC acts upon specific sites in the brain, called cannabis receptors, kicking off a series of cellular reactions that ultimately lead to the "high" that users experience when they smoke marijuana. Some brain areas have many cannabinoid receptors; others have few or none. The highest density of cannabis receptors are found in parts of the brain that influence pleasure, memory, thoughts, concentration, sensory and time perception, and coordinated movement. Not surprisingly, marijuana intoxication can cause distorted perceptions, impaired coordination, difficulty in thinking and problem solving, and problems with learning and memory. Research has shown that marijuana's adverse impact on learning and memory can last for days or weeks after the acute effects of the drug wear off. As a result, someone who smokes marijuana every day may be functioning at a suboptimal intellectual level all of the time.

4. Marijuana Use in the U.S. In 2007, there were 2.1 million persons who had used marijuana for the first time within the past 12 months; this averages to approximately 6,000 initiates per day. This estimate of past year initiates in 2007 was about the same as the number in 2006 (2.1 million), 2005 (2.1 million), 2004 (2.1 million), 2003 (2.0 million), and 2002 (2.2 million).

5. Marijuana Use and Mental Health A number of studies have shown an association between chronic marijuana use and increased rates of anxiety, depression, suicidal ideation, and schizophrenia. Some of these studies have shown age at first use to be a factor, where early use is a marker of vulnerability to later problems. However, at this time, it not clear whether marijuana use causes mental problems, exacerbates them, or is used in attempt to self-medicate symptoms already in existence. Chronic marijuana use, especially in a very young person, may also be a marker of risk for mental illnesses, including addiction, stemming from genetic or environmental vulnerabilities, such as early exposure to stress or violence. At the present time, the strongest evidence links marijuana use and schizophrenia and/or related disorders. High doses of marijuana can produce an acute psychotic reaction, and research suggests that in vulnerable individuals, marijuana use may be a factor that increases risk for the disease.

6. How many teens smoke marijuana Contrary to popular belief most teenagers have not used marijuana and never will. Among students surveyed in a yearly national survey, about one in six 10th graders report they are current marijuana users (that is, used marijuana within the past month) . Fewer than one in five high school seniors are current marijuana users.

7. 2001 723,627 2000 734,498 1999 704,812 1998 682,885 1997 695,200 1996 641,642 1995 588,963 1994 499,122 1993 380,689 1992 342,314 YEAR MARIJUANA ARRESTS

8. Effects of Marijuana on the Brain Researchers have found that THC changes the way in which sensory information gets into and is acted on by the hippocampus. This is a component of the brain’s limbic system that is crucial for learning, memory, and the integration of sensory experiences with emotions and motivations. Investigations have shown that THC suppresses neurons in the information processing system of the hippocampus. In addition, researchers have discovered that learned behaviors, which depend on the hippocampus, also deteriorate.

9. Effects of Marijuana on the Lungs Someone who smokes marijuana regularly may have many of the same respiratory problems that tobacco smokers have. These individuals may have daily cough and phlegm, symptoms of chronic bronchitis, and more frequent chest colds. Continuing to smoke marijuana can lead to abnormal functioning of lung tissue injured or destroyed by marijuana smoke. Regardless of the THC content, the amount of tar inhaled by marijuana smokers and the level of carbon monoxide absorbed are three to five times greater than among tobacco smokers. This may be due to marijuana users inhaling more deeply and holding the smoke in the lungs.

10. Other Short Term Effects Dry mouth and/or throat, problems with memory and learning, distorted perception (sights, sounds, time, touch), trouble with thinking and problem solving, loss of motor coordination, increased heart rate, and anxiety. These effects are even greater when other drugs are mixed with marijuana. Persons high on marijuana show the same lack of coordination on standard drunk driver tests as do people who have had too much to drink.

11. Long Term Effects Marijuana smoke contains some of the same cancer-causing compounds as tobacco, sometimes in higher concentrations. Someone who smokes 1 to 3 joints can produce the same lung damage and potential cancer risk as smoking five times as many cigarettes.

12. Street Name / Slang Terms Aunt Mary, Bobby brown, Boom, Chronic, Dope ganja, Gangster, Grass, Hash, Herb, Kif, Mary Jane, Pot, Reefer, Sinsemilla, Skunk, Weed ,

13. How is used Usually smoked as a cigarette or joint, or in a pipe or bong, marijuana has appeared in blunts in recent years. These are cigars that have been emptied of tobacco and re-filled with marijuana, sometimes in combination with another drug, such as crack. Some users also mix marijuana into foods or use it to brew tea.