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About cannabis (marijuana)

Last update date December 27, 2019

What is cannabis (marijuana)?

 "Cannabis" in Cannabis Control Law means cannabis grass (cannabis satiba L: Cannabis sativa L.) and the product. But mature stem of cannabis grass and the product (we remove resin.) and seed of cannabis grass and the product are removed. It is said that you possess cannabis if it is not cannabis handler (license of prefectural governors) and cultivate and obtain by transfer and hand over or you must not use for study (Cannabis Control Law Article 3). In addition, it is said that you must not do that you import cannabis or you export (case cannabis researcher receives permission of the Minister of Health, Labour and Welfare and imports cannabis or to export is excluded.) (Cannabis Control Law Article 4). It is from Article 24 of Cannabis Control Law to Article 27, and penal regulations such as imprisonment, fine for violators are established.
 In late years people arrested by violation of Cannabis Control Law increase in Japan. Please see lower graph. The annual arrest staff of cannabis criminal offense of 2009 (Heisei 21) became the previous maximum in 2,920 people. In addition, the number of annual arrests of cannabis cultivation case increased, too, and, as for the number of annual cannabis cultivation case arrests of 2009 (Heisei 21), it was 312 and the previous maximum. In cannabis cultivation case, there seems to be cultivation in commercial purpose by plastic greenhouse and outdoor culture of building for rent, house for rent, mountains other than cultivation in self-purpose of use in apartment apartments, too (references 13).
 Afterwards, decrease was seen in the annual arrest staff of cannabis criminal offense for peak until 2013 in 2009, but increased again from 2014. The annual arrest staff of cannabis criminal offense of 2018 (Heisei 30) became 3,578 and the past maximum. We are in twenties (1,521 people, 42.5%) and in our 30s (1,101 people, 30.8%), and it is a lot. Under 20 years old are 59, 80, 144, 210, 297, 429 and tendencies to increase about 25, Heisei, 26, 27, 28, 29, 30 (2013, 2014, 2015, 2016, 2017, 2018) years, too. About Heisei 25,26,27, 28, 29, 30 (2013, 2014, 2015, 2016, 2017, 2018) years, as for the university student, as for 23, 27, 31, 40, 55, 100 people, the high school student, as for 10, 18, 24, 32, 53, 74 people, the junior high student, 0, 3, 3, 2, 2, seven people and all are tendencies to increase (references 14,17). About 2015, we disclosed two cannabis abuse groups led by high school student in the Kyoto Police (the outside site) and, by September, 2015, arrested seven high school boy and others who possessed cannabis grass or drying cannabis, and did for Cannabis Control Law violation (possession) and guided ten boys (references 14).

Figure 1 cannabis criminal offense arrest staff change (1,966-2,018 years) in Japan.
Cannabis criminal offense arrest staff change (1,966-2,018 years) in Japan

 In addition, there are many stimulant criminal offenses, and the arrest staff occupies 9,868 and 71.2% of whole drug criminal offense in the year of stimulant criminal offense in 2018 (Heisei 30) when we see in the whole drug criminal offense in Japan. Like table 1 below, the annual arrest staff of cannabis criminal offense of 2018 (Heisei 30) occupies 25.8% of 3,578 people and whole drug criminal offense, and there is many next to stimulant criminal offense.

Table 1. The annual arrest number of people (people) according to 2018 (Heisei 30) drug criminal offense
DivisionThe arrest staff (people)Ratio (%)
Stimulant9,86871.2
Cannabis3,57825.8
Drug and psychotropic drugThe whole4153.0
Designer drugs such as inner MDMA500.4
Inner cocaine1971.4
Inner heroin100.1
Others inner1581.1
Opium10.0
Total13,862100.0

Materials: National Police Agency organized crime measures department organized crime measures Planning Division "situation (decision level version) of organized crime in 2018" March, 2019.

 Marijuana (marijuana) is doing green, gray and brown with mixture which dries, and chopped flower, stem, seed, leaf of cannabis grass. We may seem to have had cutting fine of dry parsley. And we bind with paper and do like cigarette or fill pipe and we set fire and may breathe smoke. We may mix cigarette with marijuana to be easy to burn. Marijuana is used in substitution for cigarette with cigar. We mix with food such as cookies and are eaten and drink as tea. There is person who uses inhalational appliance to avoid breathing smoke. With inhalational appliance, we accumulate steam with active ingredient as steam from marijuana in retention department and inhale steam.
 Smoke of marijuana is stimulating and is unique and usually smells sweet-sour. Originally marijuana is Mexican word, but it is name to be used in many countries now. Originally, in Mexico, marijuana meant cheap cigarette. This cheap cigarette mixed cannabis and might be breathed and seems to have come to gradually mean cannabis cigarette. In addition, we concentrate ingredient, and thing which we became into brown and black and green resin form may be called hash (hashish). Sticky black thing which became liquid is called hash oil (hash oil), hash oil (hashish oil) or liquid cannabis (liquid cannabis). We mix with cigarette and are breathed. Marijuana is unjust drug abused most widely in the United States.
As for marijuana, difference is seen in action by quantity taken in. For example, sedation is little quantity, and hallucination action is seen with much quantity.
 Chemical substance indicating the main action is THC (delta-9tetrahydrocannabinol: delta, 9, tetrahydrocannabinol) by use of cannabis such as marijuana. There are nerve cells having receptor for THC in brain. It is thought that as THC binds to this receptor, will feel so-called "state that is high" (high). There are at least 60 kinds to chemical substance (cannabinoids: cannabinoid) of THC resemblance in cannabis, but it is several kinds that action is accepted biologically, and it is thought that it is the strongest with THC.
 Effect of marijuana provided in the United States becomes very stronger than the old days. Effect of marijuana is shown in % of weight of THC for dry weight of marijuana. Quantity of THC included in marijuana was less than 1% at the 1970 Taizhong time, but becomes 6% or more in 2002. In addition, THC is not distributed over flower, stem, seed, leaf of cannabis grass in the same density. Bought and sold marijuana usually includes stem and seed having low density of THC. THC is the most highly-concentrated, and strong marijuana which gathered buds of female of non-pollination of existing cannabis grass is called sinsemilla (sinsemilla). Quantity of THC included in sinsemilla increases from 6% to 13% or more during the past 20 years, and there is thing to include by 33%. In addition, sinsemilla (sinsemilla) is Spanish. Shin (sin) comes from sine of Latin and means "(without -) without ...", and semirya (semilla) means "seed" (seed). Sinsemilla is provided by cultivation only for female.
 After, in the case of ingestion of THC and marijuana, taking in that the density in blood of THC becomes maximum; from one hour for 3 hours. Influence begins to appear 30-60 minutes later with we ingest, and influence usually remains until around four hours. Time when influence remains in cases with much quantity of ingesting becomes long. When we smoke marijuana, THC is absorbed from the lungs and gets in blood immediately, and blood density of THC becomes greatest when we have finished breathing. When we breathe, influence begins to appear immediately, and influence usually remains to degree for 1-3 hours. We get longer in cases with much quantity that we breathed at time when influence remains. The density in blood of THC usually falls to low level during 4-6 hours. When we breathe, THC from several times to around 10 times is absorbed and, in comparison with case that ingested the same quantity, enters in blood. Among THC which is absorbed, and entered the body, 80-90% are exhausted outside body within five days. In about 20%, about 65% are exhausted into flight into urine. After having smoked marijuana, the THC and metabolism thing is detected from all over the urine during several weeks. On the other hand, THC accumulates to internal adipose tissue from all over the blood, and accumulated THC gradually comes out of adipose tissue in blood when intake from outside the body was quitted.
 In addition, it may be used as therapeutic drug for the purpose of THC controlling feeling like vomiting of patients with cancer during chemotherapy in the United States while cannabis (marijuana) is illegal drug, and letting you increase appetite of AIDS patient consuming.
 We are made in U.S. 50 states, and, in the United States, as for marijuana, there are things made abroad such as Mexico, Canada, Colombia, Jamaica. Money that the American nation spent for the purchase of marijuana in 1999 is considered to be 10.6 billion dollars. It is said that 2.6 million people used marijuana newly in the United States of 2001. As for around 3.1 million people who passes more than one year, and uses marijuana almost every day, it is estimated that I am. Person who has used marijuana at 12-17 years old by statistics of 2002 becomes 53.8% at 20.6%, 18-25 years old. At 12, 13 years old, 26.0% of people say that it is very easy for 79.0% of people to obtain marijuana at 16, 17 years old. It is said that it is easy to use with marijuana than nonsmoker smoker.
 Cannabis is unjust drug used globally most widely. It is estimated that 181.8 million people (interval estimation: 128.5 million - 232.1 million) use cannabis at 15-64 years old throughout the world in 2013 (references 16). It is outstanding that North America, Europe, people using cannabis in developed country in Australia increased rapidly from the 1,960 years level. The arrest number of people of cannabis criminal offense increases rapidly from the 1,960 years level in Japan. Cannabis has lower start age than other illegal drugs, and ties with youth culture are thought about. It is necessary to prevent young people knowing harm of cannabis well and from using cannabis.
 Use of early empty severe marijuana of the life is tied to high utilization of low income, fewer acquisition units at university, the high need of economical support, the high unemployment rate, other drugs (references 16).
 Marijuana may be used for decreases in ko*kan, increase of sociability, shyness, embarrassment, anxiety. Besides, we demand activation of physical mark and mental work by cocaine and stimulant and demand relaxation of strain with heroin, and illegal drug may be used. At first, thing which we bought may seem to have been provided, but quantity and the number of times to gradually use increase, and serious problem occurs for everyday life and may fail.

 In the 1,990 years level beginning, cigarette smoking preceded use of cannabis in many developed countries, and it was said that smoking custom of cigarette became entrance (gateway) of use of cannabis. There are low cigarette smoking rate and high cannabis utilization and developed country where it is, and change is seen in for smoking custom of cigarette and relations with use of cannabis when it passes for the next 20 years. In Australia and the United States, young people who begin use of cannabis before beginning to smoke increase as a result of public sanitation campaign of anti-cigarette. It may be expressed with "reverse entrance" ("reverse gateway") saying that use of cannabis becomes entrance (gateway) of smoking custom of cigarette in these countries (references 16). There is common point by breathing smoke with smoking custom and use of cigarette of cannabis, and it may be in each other's entrances with both sides. Cannabis is mixed with cigarette and may be used.

 According to Australia, New Zealand in the 1,970 years level and the 1,980 years level, the epidemiologic study in the United States, cannabis user is easy to use heroin and cocaine. And it is easy to use with other drugs so that it is early to begin use of cannabis (references 16).

Harm of cannabis (marijuana)

 Show use of cannabis (marijuana) below physically mentally; various kinds of; is harmful.

Harm to brain, mind, action

 When marijuana is smoked, THC in smoke gets in blood from the lungs and circulates through whole body. A part of THC during bloodstream is combined with receptor called neuronal cannabinoids (cannabinoid) receptor of brain and affects the nerve cells. Part of brain that cannabinoids receptors are seen a lot is part related to joy, memory, thought, concentration, sense, acknowledgement at time, cooperation exercise. Abnormality is seen after the intake slowly in 1-2 hours whereas abnormality is seen rapidly when marijuana is smoked when we are ingested. Difficulty of memory, learning, thought, solution to the problem, change (change is seen in form, color, brightness and feels progress of time to be slowly) of perception, relaxation, elation of strain are talkative, and short-term influence by use of marijuana is increase of heart rate, the reinforcement of appetite. Anxiety, panic, depressed mental state, state, strange action, aggressive action, delusion, hallucination (there are many visual things) may be seen so. Even if clear mental influence remains for several hours, normal, but influence remains even if it passes for 24 hours, and what we do not continue may finally become quiet for a few days further. Depending on long-term use of marijuana, it is thought that we may have change that resembled that even other drug abuse is seen in brain. By long-term use of marijuana, the initiative loss and athymia, drop of results may be seen. By long-term use of marijuana, permanent obstacle of memory and acknowledgement occurs and seems to be strongly seen when it is particularly pubertal and starts use. Decrease in capacity of sea lion, amygdaloid body, the cerebellum is accepted in the brain by long-term use of marijuana (references 16).
 It becomes dependency of marijuana, and withdrawal symptoms may be seen. Withdrawal symptoms may appear within 1-2 days after marijuana was cut off. Withdrawal symptoms may be seen by using marijuana repeatedly even in small quantities for five days. Withdrawal symptoms lighten by oral THC and disappear (references 4). Withdrawal symptoms are short-tempered and are abnormality, inappetence, weight loss, chills, fatigue of sleep such as anxiety, depression, aggressive tendency, sleeplessness. Withdrawal symptoms go out after it reached peak in 2-3 days. Most of the withdrawal symptoms are recognized during period until 10th after marijuana was cut off, but symptom may remain even if it passes on 28th (references 5). It is difficult for marijuana habitual offender to stop marijuana by earnest desire and withdrawal symptoms to marijuana.
 In the young adult, use of marijuana causes the shrinkage of cerebral artery, and cerebral infarction or transient cerebral ischemic attack (transient ischaemic attack: TIA) may be caused. The shrinkage of this cerebral artery is dissolved within 3-6 months by stopping marijuana (references 16).
 The fatal dose of someone's THC is estimated to be 15-70 g by animal experiment, and it is thought that considerably a larger quantity of than normal consumption, sudden death by breathing stop by surplus use of cannabis (marijuana) is rare. There is not cannabinoids receptor in brainstem of brain controlling breathing, and it is thought that respiratory depression that is easy to be tied to death is hard to be caused with other drugs.
 It is thought that use of cannabis (marijuana) worsens schizophrenia and manic-depressive psychosis.

Automobile accident

 In the United States, alcohol, the second place are marijuana the first place of material which may be detected in the automobile accident that dead person produced by driver. It is seen well that alcohol and marijuana are detected, and it is said that drop of ability for driving is seen conspicuously when both are put together.

Harm to heart

 Use of marijuana lowers oxygen carrying capacity of blood. The risk that heart attack happens within one hour after use of marijuana has a study to be finished to 4.8 times (references 11).
 As for marijuana, smoke is breathed in and, during several minutes, may increase heart rate. It is 70-80 times, but we let you rise 20-50 times, and we increase to double, and heart rate may usually put a more burden on heart for one minute. Increase of heart rate may last for three hours. In people with the past with coronary disease, we may trigger anginal attack or myocardial infarction (about these adverse effects, cocaine is stronger than marijuana). In addition, blood vessel of eyes is expanded, and eyes may look red.
 We may not be seen during 2-4 weeks when we continue use of marijuana about increase of heart rate by use of marijuana every day.

Harm to the lungs, the respiratory tract

 By use of marijuana, we may produce stinging and feeling to be burnt, a severe cough of the mouth and throat. Like smoker, it becomes easy to suffer from a cough and acute respiratory infectious disease that a lot of sputa included pneumonia in. Chronic bronchitis and chronic obstructive pulmonary disease (COPD: chronic obstructive pulmonary disease) such as pulmonary emphysema may be seen. As bronchoscopic views of people breathing only smoke of marijuana, swelling and edema of bronchial mucosa narrow the bronchus, and partial confinement is seen, too. As views of biopsy of bronchial mucosa of people breathing only smoke of marijuana, fimbria cell of the normal respiratory tract decreases and is moved with viscous liquid secretion cells.
 It is said that smoke of marijuana includes a lot carcinogens such as benzopyrene (benzopyrene) 50-70% than smoke of cigarette. In addition, person smoking marijuana breathes in smoke deeply, and stop for breath, and may be going to take a lot THC in the body by keeping smoke in the lungs as long as possible, but such; breathe; of cigarette normal as for the breathe, and lengthen contact with carcinogen in the respiratory tract pulmonary than. When we smoke one marijuana in comparison with smoking one filter-tip cigarette of equal weight, quantity of tar to deposit to the lungs is said to be 4 times. If frequency to breathe is the same, breathing may be at increased risk for suffering from cancers such as lung cancer with marijuana than we smoke. In addition, person smoking marijuana has research that there is much lung capacity. It is thought that we repeat deep breathing at time to smoke marijuana.
 In addition, smoke of both is greatly different from point where THC and chemical substance (cannabinoids: cannabinoid) of THC resemblance are not included in smoke of cigarette at point where nicotine is not included in smoke of marijuana. The bronchus shrinks by breathing smoke of cigarette, but the bronchus is expanded according to quantity of THC by breathing smoke of marijuana. It is reported the bronchus expansion action of marijuana in the United States to use in marijuana alone without mixing cigarette with marijuana. In addition, smoke of cigarette activates haiho macrophage which is central immune cell in the lungs. haiho macrophage releases cytokine and promotes release of material damaging organization and causes chronic bronchitis and pulmonary emphysema. Activity of macrophage is low in marijuana users, but, according to the immunosuppressive action of THC, it is thought that we compare with cigarette smoker (references 16). It is big risk factor becoming COPD (chronic obstructive pulmonary disease) that breathes smoke of cigarette, but it seems to be small for COPD and risk factor that it is to breathe only smoke of marijuana. As abnormal finding in inspection of breathing function in people breathing smoke of marijuana, there is slight increase of the respiratory tract resistance, but, in this, according to swelling, edema of bronchial mucosa by stimulation of smoke of marijuana, it is thought.

 Pneumonia such as invasive pulmonary aspergillosis may be seen in immune controlled marijuana users. Use of marijuana spoils function of haiho macrophage playing an important role in infection defense in the lungs. Decrease in fimbria cell in bronchial mucosa and increase of viscous liquid secretion cell spoil clean action of the respiratory tract by fimbria exercise and become easy to be infected with pneumonia. In addition, cannabis may pollute in gram-negative bacteria which can become Aspergillus fumigatus and pathogen which are pathogen of pulmonary aspergillosis, and those pathogens may be breathed in in the lungs by breathing smoke (references 16).

 In the young adult, there is findings that use of long-term marijuana adds to the risk to suffer from lung cancer (references 12).

Harm to immune system

 Cannabinoids (cannabinoid :It is said to CB) receptor that there is cannabinoids -2(CB-2) receptor seen in cell participating in immunity separately from cannabinoids -1(CB-1) receptor which is frequent in nerve cells of brain (references 7). It is thought that THC and chemical substance (cannabinoids: cannabinoid) of THC resemblance inhibit immunity by being combined with CB-2 receptor of cell participating in immunity. As a result, it is thought that marijuana habitual offender is easy to suffer from infectious disease and cancer. There is findings that there are many cancer, lung cancer of the head and neck in marijuana habitual offenders.
 In addition, about CB-1 receptor, CB-2 receptor, it may be called CNR1 (cannabinoid receptor 1), CNR2 each. In addition, part of brain with many CB-1 receptors is cerebellum modifying sea lion affecting memory, amygdaloid body concerned with feeling movement reaction, cerebral cortex modifying perception, limbic system modifying will, cooperation exercise control. There is CB-1 receptor to heart, blood vessel system. About CB-2 receptor, we are concerned with activities such as gastrointestinal tract, liver, heart, muscle, skin, the sex organs as well as control of immune system.

Cancer of the testicles

 After 2009, relations with cancer of the testicles are reported with smoking marijuana in three theses published in the United States (references 16). These relations are strong in people who begin to smoke marijuana since before having become 18 years old, and smoke marijuana more than once a week. Relations with cancer of the testicles are not accepted with smoking. Cannabinoids (cannabinoid :There is CB) receptor in the testicles.

Harm to the pregnancy, fetus

 About child born from mother smoking above marijuana six times a week, the premature birth and low birth weight child tends to be seen. Fetus becomes lack of oxygen by breathing in carbon monoxide which mother produces like smoking time when marijuana burns and may receive adverse effects. About "the pregnancy and smoking" of our Yokohama City Inst. of Health web page, please refer to about about "passive smoking of child" and "sudden infant death syndrome" (SIDS) (please click underline part).

It is ... for prevention of drug abuse

 Cannabis is illegal, harmful drug not safe medicine as foregoing paragraph is "harm of cannabis" (marijuana), and wrote down. It will prevent you from yielding to temptation of cannabis. For prevention of drug abuse including cannabis, please refer to the following reference websites.

Reference website

References ...

  1. NIDA - NIH - U.S. Department of Health & Human Services. ; Marijuana: It is p.1-7. DRUG FACTS (the outside site), March 2016
  2. Luis Alfonso Nunez Dominguez, Cannabis and Psychiatric Pathology: An Update. ; The Journal of Applied Research, Vol. 4, No. 1, 2004, p.164-172.
  3. CDC, Urine Testing for Detection of Marijuana: An Advisory. ; MMWR, September 16, 1983/32 (36); p. 469-471.
  4. Margaret Haney, Carl L Hart, Suzanne K Vosburg, Jennifer Nasser, Andrew Bennett, Carlos Zubaran and Richard W Foltin, Marijuana Withdrawal in Humans: Effects of Oral THC or Divalproex, Neuropsychopharmacology (2004) 29, p.158-170.
  5. Elena M. Kouri, Harrison G. Pope Jr. ; Abstinence symptoms during withdrawal from chronic marijuana use. : Exp Clin Psychopharmacol. 2000 Nov; 8(4): p. 483-92.
  6. Budney, A.J.; Hughes, J.R.; Moore, B.A.; Novy, P.L. ; Marijuana abstinence effects in marijuana smokers maintained in their home environment. Archives of General Psychiatry, 2001:58 (10): p. 917-924.
  7. Stephen M. Stahl, Getting Stoned Without Inhaling: Anandamide Is the Brain's Natural Marijuana, J Clin Psychiatry. 1998 Nov, Vol 59 No 11, p. 566-567.
  8. NIDA - NIH - U.S. Department of Health & Human Services. ; Marijuana abuse: It is p.1-8. 2005 in NIDA research report series, July
  9. ONDCP (Office of National Drug Control Policy), Executive Office of the President, Marijuana: ONDCP Drug Policy Information Clearinghouse FACT SHEET, February 2004, p. 1-8.
  10. The National Police Agency Criminal Affairs Bureau organized crime measures department drug firearms measures section, "Drug, the firearms situation in 2004," January, 2005.
  11. Murray A. Mittleman, Rebecca A. Lewis, Malcolm Maclure, Jane B. Sherwood and James E. Muller; Triggering Myocardial Infarction by Marijuana; Circulation, June 12, 2001;103;p. 2805-2809.
  12. S. Aldington, M. Harwood, B. Cox, M. Weatherall, L. Beckert, A. Hansell, A. Pritchard, G. Robinson and R. Beasley on behalf of the Cannabis and Respiratory Disease Research Group; Cannabis use and risk of lung cancer: a case-control study. Europian Respiratory Journal. 2008, Vo. 31, No. 2: p. 280-286.
  13. The National Police Agency Criminal Affairs Bureau organized crime measures department drug firearms measures section, "Drug, the firearms situation (decision level) in 2009," April, 2010.
  14. The National Police Agency Criminal Affairs Bureau organized crime measures department drug firearms measures section, "Drug, the firearms situation (decision level) in 2015," March, 2016.
  15. NIDA - NIH - U.S. Department of Health & Human Services. ; Drug Facts: It is p.1-6. Drugged Driving (the outside site), June 2016
  16. Department of Mental Health and Substance Abuse, World Health Organization(WHO); The health and social effects of nonmedical cannabis use (the outside site); WHO Document Production Services, Geneva, Switzerland. 2016.
  17. National Police Agency organized crime measures department organized crime measures Planning Division "situation (decision level version) of organized crime in 2018" March, 2019.

January 12, 2005 publication
February 2, 2005 revision
Revision supplementary on June 4, 2010
Revision supplementary on August 26, 2016
Revision supplementary on December 25, 2019

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