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Marijuana Position Paper

Prevention Works is opposed to both the use of marijuana as a recreational drug and to the use of marijuana in smoked form as unsuitable as a medicine.

Research on the health and safety effects of marijuana strongly correlates with many mental, emotional, psychological, physical and spiritual problems. In addition, many crimes, accidents, job and school performance problems have been associated with the use of marijuana. While not everyone that uses marijuana becomes drug dependent, the reality is that as with alcohol and other drugs, marijuana use certainly can lead to profound, chronic and progressive chemical dependency.

Its use can be very serious, dangerous, and have a profound impact upon the quality of life for hundreds of thousands of Americans and their families.

The consumption of marijuana is not recommended.

For many users it causes mild-to-severe distress and it may have even more profound physical or psychological effects especially for the following: to individuals who are engaging in activities that could potentially place themselves and others at risk for personal injury such as:

Psychopharmacological Properties

Marijuana is a powerful, mind and mood altering drug. A very small amount of cannabis, i.e., 2-3 mg of THC, can produce a high for the occasional user. A single marijuana cigarette may contain as much as 20-30 mg or even more. As an hallucinogen, the effects of this drug are particularly sensitive to individual differences in personality and environment settings, and may vary widely. At moderate to high doses of THC, mood varies considerably while anxiety and panic have also been reported. Depression may also be enhanced. Impairment of short term memory, disturbances in thought patterns, lapses in attention, depersonalization, and sensory distraction also occur. Larger doses can bring on stronger distortions of time and space, illusions, mental confusion and panic reactions. Extremely large doses can cause hallucinations (5), and marijuana flashbacks have been reported by some users (6). Depending on dose and type, hallucinogens variously produce hypoactivity or hyperactivity, aggression or docility, marked autonomic stimulation, incoordination, and hypersensitivity to sensory stimuli. These compounds alter the electroencephalogram tests in both animals and humans (7).

THC interferes with the normal functioning of the cerebellum, the hippocampus and portions of the cerebrum (8). Animal studies have shown an accumulation of THC stored in the synaptic vesicles of the brain cells. This results in a thickening of the cell wall and synaptic cleft (perhaps hundreds of times thicker than normal). This profoundly slows the transmission of neurotransmitters and causes interference of the delivery at the receptor site (9).

Physical Dangers of Marijuana Use

Research has consistently demonstrated that there are potentially serious and damaging physical effects from marijuana use and abuse.

There is documented evidence that marijuana typically causes acute changes in the heart and circulation. It increases the work of the heart, usually by raising the heart rate by as much as 50%, and in some people by raising blood pressure. While these effects may only be temporary, it increases the need for oxygen to the body while at the same time decreasing the supply of oxygen.

This places a threat for persons with hypertension, cerebrovascular disease, and coronary atherosclerosis (10). Research indicates that it may be especially dangerous for cardiac patients to combine marijuana with alcohol (11). In fact, the National Academy of Science Institute of Medicine recommends that persons with cardiovascular disease avoid the drug (12). Dr. Ronald I Herning and Dr. Jean Lud Cadet, with colleagues at NIDA's Intramural Research Program in Baltimore, report preliminary evidence suggesting that chronic abuse of marijuana can restrict blood flow to the brain and increase the risk of stroke 12 (a).

Smoking marijuana can lead to worse results for the lungs than smoking tobacco (13). There is nearly five times more carbon monoxide and three times as much tar inhaled into the lungs when one smokes a marijuana cigarette as opposed to a tobacco cigarette (14). Marijuana smokers may suffer bronchitis, emphysema, and bronchial asthma (15). Marijuana users are twice as likely to report symptoms of chronic lung disease as non-users (16), and one finding showed that men who smoked only marijuana on a regular basis displayed airway obstruction. Marijuana smoke produces 50% more hydrocarbons than tobacco smoke. Hydrocarbons are the chemicals associated with lung cancer. In fact, marijuana smoke contains 50% more cancer causing materials than tobacco smoke (17), and has been linked to both pre-cancerous growths and to cancer (18) (19).

Heavy use of marijuana may affect the endocrine or hormonal systems of both men and women causing reduced levels of testosterone, lowered sperm count, impotence, and gynecomastia (development of the mammary glands) in men, and disrupted menstrual cycles in women (20). Furthermore, high doses over a period of time can lead to depression of libido and impotence (21). In both animal and human studies, heavy use of marijuana was found to possibly interfere with the T-lymphocyte part of the immune system, reducing resistance to viral infection and cancer (22). Cannabis can also inhibit the intracellular synthesis of proteins DNA and RNA, and inhibit cell division, similar to alcohol and the opioids (23).

Amotiviational Syndrome

Clinical evidence suggests a correlation between chronic use of marijuana and the development of a syndrome characterized by a marked decrease in personal drive, motivation and ambition, with apathy about the future, lethargy, shortened attention span, high distractibility, decreased concentration, and an overall impairment of judgement and memory of the chronic user (24). Very regular high doses of cannabis may be associated with significant psychological adjustment problems in some users (25). It is unclear whether the development of an amotivational syndrome is a causative factor of heavy use of marijuana or an effect of chronic use. Conservatively, it has been suggested that heavy use of marijuana may increase the likelihood of the development of the syndrome, and that the syndrome does reinforce the chronic use of marijuana (26).

Mental Illness and Associated Dangers of Marijuana Use

Research has long implicated cannabis as an exacerbating factor in mental illness where mental illness and/or personality problems are pre-existing or concurrent conditions. Recent research has largely supported these earlier findings.

One study found that the severity of depression and anxiety symptoms increased progressively with the degree of involvement with cannabis, and chronic use of cannabis was associated with a high prevalence of co-morbid psychiatric disorders (27). Other studies demonstrated that cannabis use predicted an increased risk of developing clinical psychosis, and cannabis users showed higher scores on schizotypy, borderline and psychoticism scales than never-users (28); that the risk of developing schizophrenia among heavy users was six times greater than among non-users (29); that for highly introspective individuals, marijuana use was associated with self-reports of poorer adult mental health (30); that greater dependence on alcohol and marijuana was found to be one determining factor predicting worse outcomes for youth in areas of criminality, conduct disorder, depression, and attention-deficit/hyperactivity disorder (31); and that substance dependence (including cannabis) related significantly to suicide attempts and self-injury histories of youth (32). Other studies have implicated marijuana use in depression (33); panic reactions and suicide (34) (35) (36); and anti-social personality characteristics (37) (38).

The American Psychiatric Association demonstrates the seriousness and severity of marijuana effects beyond simple cannabis intoxication. They include Cannabis Intoxication Delirium, Cannabis Induced Psychotic Disorder with Delusions, Cannabis Induced Psychotic Disorder with Hallucinations, Cannabis Induced Anxiety Disorder, and Cannabis Related Disorders not Otherwise Specified (39). The Cannabis related mental disorders are quite serious, and many people find themselves as chronic clients in mental health programs or as mentally ill chemical abusers because of the effects of marijuana.

Marijuana and Job Performance, School Performance, Driving, and Crime

Employees who are marijuana users were found less likely to commit to their organizations, had less faith in management, and experienced more job dissatisfaction (40). These workers reported more absenteeism, tardiness, accidents, worker's compensation claims, and job turnover than workers who did not use marijuana. They were also more likely to report to work with a hangover, miss work because of a hangover, and be drunk or use other drugs at work (41).

In terms of school, studies have found that college students who use marijuana regularly had impaired skills related to attention, memory and learning twenty-four hours after they had last used the drug, suggesting that marijuana users may be limiting their ability to learn. Evidence especially shows that heavy marijuana smoking impairs the cognitive processes (42). Heavy marijuana users, when compared to non-users, show impaired cognitive functioning across the board, and significant impairment in mathematics (a measure of the ability to do quantitative thinking), and in verbal expression (a measure of correct and appropriate word use).

Heavy users showed a trend toward impairment in selecting synonyms, in literary comprehension, or overall ability to learn (not just when "high", but a lingering loss of cognitive skills after the high is gone) (43). Animal studies show structural damage to the hippocampus, a structure critical in learning and memory, from the principle ingredient in marijuana (THC) (44). A major study in New York demonstrated that 51 percent of marijuana using college students engaged in some form of "public misconduct" and 37 percent of users reported "serious personal problems" due to marijuana use (45).

In terms of driving, marijuana use impairs driving-related functions and there is a definite increased risk for auto accidents with use of marijuana (46). It impairs motor coordination, alters sense of time and distance, and makes one drowsy. One study demonstrated severe balance impairment and 2.5 times more errors in coordination tests in a dose-response fashion (47). One study showed that from 4-to-12 percent of fatal and non-fatal accident victims had marijuana in their bloodstream, and another study showed that 32% of drivers in a Baltimore Shock Trauma Unit had marijuana in their bloodstream.

Marijuana use is definitely related to crime. In Omaha, 42% of all males arrested in 1995 tested positive for marijuana; in San Diego 35% of males arrested tested positive; and in Chicago 41% of arrestees tested positive for marijuana in 1995 (48). In fact, the percentage of male arrestees testing positive for marijuana was equal to or greater than that of cocaine in 13 of 23 Drug Use Forecasting cities studied (49).

Additionally, a new study has found a connection between marijuana use and crime among 18-20 year olds, according to a Alcoholism & Drug Abuse Weekly. The study found that the marijuana-use rate among young arrestees rose steadily from 25 % in 1991 to 57 % in 1996, and remained at 60% through the rest of the 1990's (49a).

Dangers of Marijuana Dependency

The classic definition of addiction includes: tolerance, withdrawal, loss of control, unsuccessful or failed attempts to abstain or control use, craving, pre-occupation with use, and use despite adverse consequences (use despite psychological, social, legal or personal consequences). From any and/or all of these perspectives, marijuana is a drug of addiction.

Marijuana is significantly more potent than it was in the sixties, making the drug even more addictive. In 1994, a U.S. Court of Appeals ruled that marijuana should remain a Schedule I drug as it is highly addictive (50).

While tolerance to marijuana and psychological dependency are commonly accepted as serious syndromes of marijuana use, some heavy users of marijuana show signs of withdrawal. In one study marijuana withdrawal subjects demonstrated restlessness, loss of appetite, trouble sleeping, weight loss, and shaky hands (51). Physical dependence on cannabis may develop in those who use high doses daily, and abrupt termination of use can produce a mild withdrawal syndrome with symptoms including sleep disturbance, irritability, loss of appetite and consequent weight loss, nervousness, anxiety, sweating, and upset stomach, chills, increased body temperature and tremors can occur. The withdrawal sickness usually lasts for less than a week, although the sleep disturbances may persist for a longer period (52).

One treatment program demonstrated that two-thirds of cannabis-dependent patients reported withdrawal, and most claimed serious problems from the cannabis (53). Progression from first use to regular cannabis use was found as rapid as tobacco progression, and more rapid than that of alcohol, suggesting that for this population - that the drug potently reinforces cannabis-taking, producing both dependence and withdrawal (54). As for the potency of marijuana dependence, many dependent users state that it is "impossible" for them to quit. In a study including people who use both cocaine and marijuana, many stated that giving up the use of marijuana was in some ways more difficult than giving up the cocaine use (55). In all, it is estimated that about 10% of marijuana users become chemically dependent upon the drug during their years of heaviest use (56). While many researchers believe that marijuana is a mildly physiological addictive substance studies do indicate that marijuana is harder to kick than many suspect (57), and is as powerful as other drug addictions (58).

Marijuana Effects on Maturation Process

Adolescence is a time of life when mind and body are maturing, and when social and emotional mechanisms of adjustment are being formed. As use of marijuana generally begins during teen years, risk of impaired emotional growth and development is of crucial concern. Many psychiatrists have expressed concern that regular marijuana use by youth produces adverse effects on psychological maturation (59). It has long been said that emotional development ceases at the time one begins marijuana use. Although not definitive, studies have shown that use may increase the risk of discontinuing high school education and of increasing job instability in young adulthood (60), and these effects upon development may cascade throughout young adult life and impact upon the quality of life of the user (as an adult) and/or their children (61).

Marijuana Related Birth Defects

Studies show that marijuana may seriously affect fetal development. Lower birth weights, a shorter gestation period, major malformations, and the occurrence of miscarriages increases with marijuana use (62). There is a risk of harm after birth for breast-feeding infants if their mothers use marijuana as it passes through breast milk in almost pure form to the infant (63). Even prior to conception, marijuana use causes changes in both males and females. It causes a decrease in testosterone, produces fewer sperm, and produces sperm with more abnormal chromosomes for the fathers-to-be. In addition marijuana may produce more testosterone and tended to produce less healthy eggs in females. With poorer quality eggs and sperm with abnormal defects there is an increased occurrence of birth defects. Marijuana also interferes with cell division, a process crucial for reproduction for healthy fetal growth and development (64) (65). One laboratory study of pregnant rats exposed to cannabis produced less fertile offspring with smaller reproductive organs (66), and another study demonstrated that embryonic development may be halted before the three-day stage suggesting that embryos are prevented from attaching to the uterine wall if exposed to marijuana (67). While studies demonstrate mixed findings, moderate marijuana use was found to be related to increased risk of ocular hypertelorism and epicanthus; and other studies have suggested that there may be significant (although temporary) differences in the behavior patterns and nervous systems of infants whose mothers frequently used marijuana during pregnancy (68). Preliminary findings from a 15 year study indicate that prenatal exposure to marijuana impairs decision making, future planning, cognition (reasoning and memory) and sustained attention among children who were marijuana-exposed babies (69)

Issues for Further Discussion

Medical marijuana

The Council supports more medical research regarding the clinical use of marijuana, consistent with the recently published study by the Institute of Medicine. It is important to note that marijuana is not a cure for any condition, but is for the management of symptoms. Use should only be under the auspice and regulations of the F.D.A. and there may be other more appropriate medicinal alternatives than the use of marijuana.

Only a small percentage do smoke marijuana

According to the 1996 National Household Survey on Drug Abuse, only 8.6% of Americans smoked marijuana in the past year... and of those who have used it a significant percentage have quit never to use marijuana again!

The “pro-marijuana” literature

Don't be mislead by all the pro-marijuana literature that's available. Our review of that literature suggests that much of it is written from a biased point of view and is suspect, misleading, or dismisses accurate findings by confusing or negating primary factors.

Marijuana use will definitely increase if it's legalized

Accessibility and availability are prime determinants in the level of drug use and as marijuana use increased with decriminalization, experts acknowledge that it will most certainly dramatically increase if legalized.

Denial

Chemically dependent people protect their drug use, and denial is one of the preferred defense mechanisms in all chemical dependencies. We often hear, "I don't have a problem" or "People over-react to marijuana" or "I can control the use" or "It doesn't have any bad effects." Denial is often profound but frequently others can see what chemically dependent individuals fail to see or recognize themselves.

Synergism

Research suggests that marijuana "reacts" with other substances in a synergistic manner, thereby making "mixing drugs" even more dangerous to life, health and safety.

Chemical dependency and treatment

As with alcohol and all drugs, marijuana can certainly lead to chronic and progressive chemical dependency. With treatment and a good 12-Step program people can and do recover. We strongly encourage those who are dependent and their families to access the available programs in their region, and we encourage government to make more prevention and treatment programs available and affordable - especially to those within the criminal justice and human service delivery systems.

Prevention

The Council supports ongoing discussion around national, state and local policies pertaining to drug abuse (including insurance and health care issues, criminal justice, workplace, child welfare, etc.) and development of prevention education, intervention and treatment services.

Parental marijuana use increases risk of use by child

A new government study found that children whose parents used marijuana are more likely to use the drug as well. The study by the Department of Health and Human Services was conducted by federal researchers between 1979 and 1996 and included surveys of 9,463 parents and children. The study found that parents who used marijuana multiple times and don't view the drug as risky were more likely to have children who felt the same way. (61) A

Research and Fact Sheet Citations

(1) Year-End 2001Emergency Department Data from the Drug Abuse Warning Network; (2) Department of Health and Human Services, Substance Abuse and Mental Health Services Administration, DHHS Publication (SMA 00-3465, 2000); (3)2001 Monitoring the Future Study; (4) American Journal of Psychiatry, December 2000; (5) Drugs - Third Edition, Schlaadt, Shannon, Prentice Hall, 1990; (6) Marijuana and Health, Ninth Report to U.S. Congress; (7) Modern Synopsis of Comprehensive Textbook of Psychiatry/II, Freedman, Kaplan, Sadock, Williams and Wilkins; 1980; (8) Mind Over Matter, National Institute on Drug Abuse publication #98-3592, December 1997; (9) Marijuana in the Nineties, D. Ohlms, MD, AMS Video Resources; (10) Drugs - Third Edition, Schlaadt, Shannon, Prentice Hall, 1990; (11) Side Effects of Simultaneous Alcohol and Marijuana Use, Sulkowski, Vachon, American Journal of Psychiatry; 134, June 1977; (12) Drugs in Society: A Biological Perspective, Jones-Witters, Witters, Wadsworth Health Services, 1983; (13) Marijuana: Right Stuff, Harvard Medical School Health Letter 14, November 1988; (14) Drugs - Third Edition, Schlaadt, Shannon, Prentice Hall, 1990; (15) Drugs of Abuse, US Department of Justice Drug Enforcement Administration, 1997 Edition; (16) Marijuana: Right Stuff, Harvard Medical School Health Letter 14, November 1988; (17) Marijuana and the Lungs, Doyle, American Lung Association Bulletin No. 65, November 1979; (18) Marijuana, W.R. Spence, MD, Health Edco, 1992; (19) Marijuana in the Nineties, D. Ohlms, MD, AMS Video Resources; (20) The Encyclopedia of Psychoactive Drugs: Marijuana - Its Effects on Mind and Body; Hermes, Galperin, Chelsea House Publishers; 1992; (21) Drugs in Society: A Biological Perspective, Jones-Witters, Witters, Wadsworth Health Services, 1983; (22) Drugs in Society: A Biological Perspective, Jones-Witters, Witters, Wadsworth Health Services, 1983; (23) Drugs in Society: A Biological Perspective, Jones-Witters, Witters, Wadsworth Health Services, 1983; (24) Skinner, M.H., Thompson D.A., Pharmacologic consideration in the treatment of substance abuse, South Medical Journal 85 (12) 1207-19,1992; (25) Drugs and Drug Abuse, A Reference Text, second edition, Addiction Research Foundation, 1987; (26) Drugs and Drug Abuse, A Reference Text, second edition, Addiction Research Foundation, 1987; (27) Psychiatric Symptoms in Male Cannabis Users not using other Illicit Drugs, Troisi, Pasini, Saacco, Spalletta, Addiction, 93(4) April 1998; (28) Cannabis use correlates with schizotypy in healthy people, Williams, Wellman, Rawlins, Addiction, 91(6), June 1996; (29) The human toxicity of marijuana, Nahas, Latour, Medical Journal of Australia 156(7), April 1992; (30) Marijuana use, introspectiveness, and mental health; Zablocki, Aidala, Hansell, White; Journal of Health and Social Behavior 32(1); March 1991; (31) Substance-dependent, conduct-disordered adolescent males: severity of diagnosis predicts 2-year outcome, Crowley, Miikulich, MacDonald, Young, Zerbe, Journal of Drug and Alcohol Dependence, 49(3), February 1, 1998; (32) Treated delinquent boys substance use: onset, pattern, relationship to conduct and mood disorders, Young, Mikulich, Goodwin, Hardy, Martin, Zoccolillo, Crowley, Journal of Drug and Alcohol Dependence, 37(2) February 1995; (33) Correlates of Depression in Primary Care, Rowe, Fleming, Barry, Manwell, Kropp, Journal of Family Practice, 41(6), December 8, 1995; (34) Health aspects of cannabis, Hollister; Journal of Pharmacological Review, 1986, 38(1); (35)The general pharmacology of cannabinoids in eds Cannabis and its derivatives, Paton, Pertwee, Temple, Oxford University Press, 1972; (36) Neurobiology of marijuana abuse, Abood, Martin, Trends in Pharmacological Sciences, 13(5), May 1992 (9); (37) The association of anti-social personality symptoms with marijuana abuse/dependence. A Monozygotic co-twin study, Scherrer, Lin,Eisen, Goldberg, True, Lyons, Tsuang; Journal of Nervous and Mental Disorders; 184(10); October 1996; (38) Anti-social behavior: Its relation to Selected Sociodemographic Variables and Alcohol and Drug Use Among Mexican Students, Substance Use and Misuse, Vol 33 (7)1998; (39) Diagnostic and Statistical Manual of Mental Disorders, 4th Edition, American Psychiatric Association, 1994; (40) NIDA Notes, Jan/Feb 1996; (41) Ibid; (42) NIDA Notes Nov/Dec 1995; March/April 1996; (43) Effects of Chronic Marijuana Use on Human Cognition, Block, R. & Ghoneim, M., Psychopharmacology, Vol. 110, 1993; (44) NIDA Notes May/June 1996; (45) Alcohol and Drug Use Among College Students in New York State, NYS Office of Alcoholism and Substance Abuse Services, 1996; (46) Lancet Heath News, 14th Issue, Nov. 13, 1998; (47) NIDA Addiction Research Center Report; (48) Reality Check, Marijuana Backgrounder, Prevention Pipeline, January/February 1997; (49) Drugs and Crime, Drug Abuse Update, National8888 Families in Action, Issue 62, Fall 1997; (49A) Alcoholism & Drug Abuse Weekly, July 2, 2002; (50) Say it straight: The Medical Myths of Marijuana, Community Anti-Drug Coalitions of America; (51) Marijuana: Facts Parents Need to Know, National Institute of Drug Abuse, revised November 1998; (52) Drug and Drug Abuse, A Reference Text, Second Edition, Jacobs and O'B.Fehr, Addiction Research Foundation; 1987, (53) Cannabis Dependence, Withdrawal, and Reinforcing Effects Among Adolescents with Conduct Symptoms and Substance Use Disorders; Drug and Alcohol Dependence, Vol. 50(1), 1998; (54) Ibid; (55) Strategies for breaking marijuana dependence, Zweben, Oconnell, Journal of Psychoactive Drugs, 24(2), April-June 1992; (56) Adverse Effects of Cannabis, Hall, Solowij; Lancet 1998, 352; (57) Smoking Pot: The Hidden Addiction, Japenge, A., Los Angeles Times, May 29, 1991; (58) Marijuana: Hit Below the Belt, Waite, K., Listen, 43(6), 1990; (59) New York State Division of Substance Abuse Services; (60) Newcombe and Bentler, 1988, as reported in World Health Organization Project on Health Implications of Cannabis Use, 1999; (61) World Health Organization Project on Health Implications of Cannabis Use, 1999; (62) Holister, L.E., Health Aspects of Cannabis, Pharmacological Reviews, American Society for Pharmacology and Experimental Therapeutics, 1986; (63) Holister, Health Aspects of Cannabis; (64) Cocaine, Marijuana, Designer Drugs: Chemistry, Pharmacology and Behavior, Redda et al., Florida, CRC Press, 1989; (65) Jones, R.T., Marijuana: Health and Treatment Issues, Psychiatric Clinics of North America, 1984; (66) Holister, Health Aspects of Cannabis; (67)as reported in Substance Abuse Funding News, October 28, 1996, No. 96-20; (68) the Ottawa Prenatal Prospective Study as reported in the Encyclopedia of Psychoactive Drugs: Marijuana: Its Effects on Mind & Body, Chelsea House Publishers, 1992; (69) Prenatal Exposure to Tobacco and Marijuana: Effects During Pregnancy, Infancy and Early Childhood, Fried, Peter, Clinical Obsteretics and Gynecology, 36:319-337, 1993.

Research and original position paper provided by the Council on Alcoholism and other Chemical Dependencies of the Finger Lakes and reprinted with permission.