Cannabis

Cannabis is the Latin term for the hemp plant. In connection with intoxicants, colloquial speech often speaks of “marijuana” or “hashish,” although strictly speaking, these are processed cannabis products. It is often difficult to determine whether it will ultimately be used as a drug or medicinal product.

The plant species from the hemp family contain active ingredients that interact with the so-called endocannabinoid system in the human nervous and immune system and thus achieve various effects. The main active ingredient, which is also responsible for the psychoactive effects, is tetrahydrocannabinol, THC for short (one of more than 60 cannabinoids). However, you can find it in all cannabis strains; for example, there are negligibly small amounts of THC in industrial hemp or some medicinal varieties. In addition, cannabis contains several other substances, such as CBD (cannabidiol) or CBN (cannabinol). Cannabis is the most commonly used illegal drug in Germany, Austria, and Switzerland.[1]

Term Origin

The widespread term cannabis comes from Latin and means “hemp.” According to the Oxford Dictionary, cannabis derives from the Mexican word “Nahuatl,” meaning “prisoner.” Colloquial names for this plant genus are pot or grass.

The cannabis plant

As already described, the cannabis plant and the hops belong to the hemp family. There are over a hundred different types of cannabis, all with other characteristics varying wildly in size, growth speed, and THC content. As a rule, the plant grows from a sprout to a plant ready for harvest within a year. The smallest species grow to about 60 cm; the largest can even reach a height of 8 meters. Characteristics of the cannabis plant are the finger-shaped leaves and finely serrated edges. The number of leaflets on a leaf will vary depending on genetics and environmental conditions. Usually, these consist of seven to nine individual leaves. The cannabis or hemp plant consists of the following individual components:

  • fibers
  • seed
  • leaves
  • blossoms

One can find trichomes (plant hairs) on the sepals and bracts of female plants, which release cannabinoids (such as cannabidiol), terpenoids (a group of natural compounds), and other volatile substances.

Cannabis Species

Male and female plants

One can divide cannabis into male and female plants. Only the unfertilized female plant is used for the intoxicating effect, especially since the highest concentration of the active ingredient, THC, can be found in the flowers.[2][3]

Botanical Outline

You can divide hemp into the following three types:

However, this breakdown is controversial; It is partly assumed that Cannabis indica and Cannabis ruderalis are not separate species or only subspecies of Cannabis sativa, which can be divided into other varieties and wide other varieties.

The ratio of CBD to the main active ingredient, THC, is higher in Indian hemp (Cannabis indica) than in ordinary hemp (Cannabis sativa).[4] However, this also depends on the time of harvest.

Although no importance is attached to ruderal hemp for producing intoxicants, since it has a low proportion of active ingredients, it is interesting for crossbreeding due to its resistance to environmental influences.

Production

By crossing the species mentioned, several hundred other varieties have been bred. This is referred to as hybrid cannabis. These breedings were carried out both to maximize the THC content of certain types (referred to as “gene hemp”) and to reduce the active ingredient content as much as possible (“useful hemp”) to achieve economic and legal use of it.

Genetically engineered hemp (although bred without genetic engineering) has female flowers with a THC content of over 20%. This high content of highly bred varieties one can usually only achieves through indoor growing.

Cultivation

There is a worldwide growth of cannabis. However, the primary producers include India, Morocco, Pakistan, Lebanon, and Afghanistan. The latter was considered the world’s largest producer of cannabis in 2010, with an estimated harvest of 1,500 to 3,500 tons (according to the “Afghanistan Cannabis Survey“).[5] Cultivation is illegal but plays an important economic role. Most of the cannabis harvested is exported as hashish. Other important cannabis-growing countries are Jamaica, Colombia, Nigeria, Thailand, and Turkey.

Indoor growing

It is the cultivation of cannabis in greenhouses, for example, using grow boxes. Indoor cultivation is punishable in Germany and Austria, even if its exclusively for personal use.

Outdoor growing

Outdoor growing is the cultivation of cannabis outside of greenhouses. Growing cannabis outside greenhouses is similar to growing industrial hemp and has fewer energy requirements than growing indoors.

Products

The two most common cannabis products are marijuana and hash. Then there is hash oil, the most potent natural hemp product. These are cannabis products as intoxicants. The so-called CBD oil is also from cannabidiol which is in cannabis or CBD.

Marijuana

Marijuana (hemp) is understood to mean dried plant parts, mainly from the unfertilized female inflorescences of the hemp plant cannabis. “Gras” or “Weed” are also typical in colloquial German. Marijuana must be distinguished from hashish, a cannabis product, but it’s pressed resin.

The intoxicant is usually smoked or inhaled after vaporization. It is often consumed orally (through food). The content of tetrahydrocannabinol (THC) depends, among other things, on the cannabis variety and ranges between 2 and 20%; with specific types (and the best conditions), even more than 25% active ingredient content is possible. The content of cannabidiol (CBD) in medical cannabis in Germany is between less than 0.05 and 10.2 percent.[6]

Hashish

Pressed resin from the female hemp plant is called hashish (hemp resin). This is usually an extract pressed into slabs or blocks. The terms “hash,” “shit,” and individual pieces, also known as “pieces,” are also widespread. The hashish is smoked, vaporized, or previously dissolved in fat for drinks or food preparation. The THC content of hashish seized by police in Europe in 2015 ranged from 4 to 28%.

Hash oil

Like hashish, hash oil (hemp extract) is obtained from the inflorescence resin of the female hemp plant. It is extracted with solvents and is not oil in the chemical sense. It is also often referred to as hash oil or THC oil.

Hash oil is very high in THC (up to 80%) and is smoked, vaped, sucked, or consumed with food or drink.

CBD oil

CBD oil is a hemp extract from legal cannabis varieties, which contains many different cannabinoids, especially CBD – cannabidiol. The cannabinoid THC is contained in a concentration of up to 0.2%. While THC induces psychoactive effects, CBD oil does not cause any psychoactive effects. It is considered healing and pain-relieving and, according to studies, is said to be helpful in diseases such as schizophrenia, epilepsy, and diabetes.

Consumption

Cannabis consumption can take place in many different ways; however, only absorption via the lungs or the stomach is common. The time between ingestion and onset of intoxication varies from a few minutes for ingestion through the lungs and between 30 and 60 minutes for ingestion.[7] The duration of action when inhaled is about two to three hours and significantly longer when consumed orally.

  • As a joint: hashish or marijuana is smoked pure or mixed with tobacco. Smoking is considered the most common form of consumption of the psychoactive compound in cannabis: THC.
  • Via a vaporizer: However, cannabis can also be vaporized and inhaled using a vaporizer
  • Via a pipe or bong: In addition to joints, unique smoking accessories such as pipes, water pipes, or bongs are also used.
  • As oil: The hash oil described above (obtained from the resin of the hemp plant) is drizzled onto cigarettes, for example, and is often added to drinks or food. It is not to be confused with CBD oil.
  • As an infusion: Cannabis can also be dissolved as tea and consumed.
  • As food: Consumption often takes place through food intake. Foods such as muffins, cakes, etc. that contain THC often have a more substantial effect than a comparable dose that is smoked.

How cannabis works

The so-called endocannabinoid system in the human body fulfills essential protective functions, helping regulate various processes. It controls feelings of happiness, relaxation, and the perception of pain, among other things, and performs an essential role for the immune system. This system includes different cannabinoid receptors; of these, there are two main types, the CB1 and CB2 receptors.

Substances from the cannabis plant, such as THC and CBD, dock onto these receptors, interact with them, and consequently affect them.

While CBD does not directly interact with the receptors and nevertheless has an enormous impact on many different conditions and diseases, the cannabinoid THC directly attacks these receptors and thus causes a state of intoxication.[8][9]

Effects of CBD

The effects of cannabidiol, or CBD for short, promise enormous medical benefits. It has many beneficial mechanisms of action and exhibits healing properties; therefore, it is highly regarded in alternative medicine. Among other things, it is known for its calming, anti-inflammatory, and anti-depressive effects. Genes responsible for various metabolic processes, fat absorption, and insulin sensitivity interact with the receptors relevant to CBD; therefore, a CBD treatment could also be helpful in these matters.

Effects of THC

When consuming cannabis, parts of the brain are stimulated, which causes the release of the hormone dopamine, which in turn can lead to a wide variety of conditions. The broad spectrum of psychological effects is very characteristic of the impact of THC in cannabis. The effect depends on a variety of factors. These include the following: the form of consumption (smoking, eating), the technique of consumption (depth of inhalation), the amount consumed, THC content, and psychological or psychosocial factors.

Possible effects of intoxication can be divided into immediate psychological and physical effects.

Mental effects: impairment of the ability to react and concentrate as well as logical thinking, relaxation, perception is changed, and much more.

Physical effects: increase in heart rate and blood pressure, cravings, dry mouth, etc.[10]

Risks

Whether and to what extent THC is dangerous to health cannot be answered in general, or many factors influence it. Among other things, the risks, such as mental disorders, depend heavily on the social environment in which the consumer is and how old he is. The personal condition, amount, frequency, and reasons for consumption are also relevant.

Risk of accidents
Since the ability to react is impaired, an increased risk of accidents must be expected under the influence of cannabis.

Mixed-use
Quite unpredictable effects can occur if you consume cannabis with alcohol, medication, or other drugs.

Mental disorders
If someone has a predisposition to mental disorders (e.g., schizophrenia), the consumption of THC can promote the onset of this.

Damage to health
If you smoke cannabis, there is an increased risk of cancer and damage to the lungs and respiratory tract.

Criminal consequences
THC is, in many countries, an illegal substance; therefore, one must expect criminal consequences when using it. Note: Since March 2017, seriously ill patients in Germany have been allowed to use cannabis as a medicine under certain conditions – for example, to treat pain and nausea caused by cancer and multiple sclerosis.

Overdose
Although it is almost impossible to die from a THC overdose – not a single death has been recorded[11] – excessive cannabis consumption can lead to unpleasant effects.

Effects of overdose

  • nausea and vomiting
  • Panic, fear, paranoia
  • impaired concentration
  • impairment of motor skills

Mixed-use

Mixed consumption is the simultaneous or immediate consumption of several addictive substances; their spectrums of action can sometimes overlap. As a rule, the effect is not the sum of all individual results; instead, the effects are amplified (potentiated) or suppressed. A combination of several substances with a psychoactive effect can trigger unpleasant and sometimes (life-)threatening interactions. Even with a mixed-use of cannabis with other drugs, there is sometimes a mutual influence.

Tobacco

According to one study, when cannabis and tobacco are used together, a cannabis user who has never smoked tobacco before can develop nicotine addiction. While the substance nicotine suppresses the THC effects of cannabis, THC, conversely, enhances the effects of nicotine.[12]

Alcohol

The interaction of cannabis and alcohol amplifies the effects of the alcohol; nausea and even fainting can also occur. Necessary warning signals from the body can no longer be adequately perceived. The collaborative consumption of these intoxicating substances is classified as hazardous to traffic. The reason for this is that the opposite effect of alcohol (which increases risk) with the hallucinatory depressant THC in cannabis increases the risk of accidents many times over.[13]

Caffeine

A study of squirrel monkeys showed that co-using cannabis and caffeine reduced the effects of THC enhanced.[14]

Opiate

Even if THC and opiates are consumed together, an increase in the main active ingredient in the plant cannabis must be assumed.[15]

The information does not claim to be complete. If a combination of substances is not listed here, this does not mean it is safe to consume.

Consequences of cannabis use

Research has often produced conflicting results regarding the psychological, social, and physical risks of long-term and frequent cannabis use. A variety of possible long-term consequences have been studied. The following are known so far:

Physical consequences

  • Impairment of lung function
  • Impaired cognitive performance (including concentration, attention, and memory)

Cannabis consumption does not cause severe brain damage, as is well known with alcohol. In any case, the effects of cannabis consumption during pregnancy and on the newborn are controversial. There is also a lack of clear research evidence of the influence cannabis has on the hormone and immune systems.

Psychological and social consequences

Research suggests that cannabis, especially at high THC doses, can trigger psychotic symptoms. These usually disappear after a few days. However, an independent “cannabis psychosis” could not be proven. Instead, one proceeds from the assumption that a hitherto hidden psychotic illness is likelier to break out in susceptible cannabis users than in abstainers.

Furthermore, general withdrawal tendencies can go hand in hand with consumption. In the context that those affected are indifferent to everyday tasks, one speaks of the “amotivational syndrome.” Today, however, this one-dimensional cause-and-effect relationship is no longer considered tenable. Rather, the person’s characteristics can be identified to explain the state of mind.[16][17][18]

Cannabis addiction

Cannabis addiction manifests itself as an unsuccessful attempt to reduce or stop use. Regular use can lead to psychological and mild physical dependence, although not everyone who uses hemp for a long time becomes dependent.

Instead, the focus is on various factors (e.g., psychosocial) that increase the risk of addiction. The extent to which these psychosocial risk factors are present is significant. So someone can be more or less at risk of developing a (cannabis) addiction. In many cases, the fundamental problem is not the substance’s effect but the psychological problem.[19]

In the case of psychological dependence, the following withdrawal symptoms can also occur:

  • joylessness
  • irritability
  • sleep disorders
  • fears

Cannabis has long been discussed under the so-called “gateway drug” term. The plant has been blamed for the fact that almost all heroin addicts were early cannabis users. Conversely, however, this does not apply to cannabis users: only a minimal proportion of them switch to other drugs.

History

The hemp plant Cannabis Sativa is one of the earliest plants cultivated by humans. In the Near East, this was used as a medicinal, cult, intoxicating, and valuable plant. Studies assume that they existed in China as early as 4,000 years BC was grown. Obtained from the stalks of the cannabis plant, fibers for cords, ropes, paper, and textiles could be made. The historical development of cannabis can be separated into its development for medical use and its history as an intoxicant.[20]

Cannabis as a medicine

A 4,700-year-old Chinese textbook on botany and medicine found records of the medicinal use of cannabis and the cannabinoids it contains.

There are 2,400-year-old reports from India that also write about the active ingredients of the cannabis plant, which were used for medicinal and ritual purposes. Records from that time describe the use or treatment of epilepsy and pain.[21]

The First Crusade, which took place from 1096 to 1099, brought cannabis to Europe and thus introduced it into folk medicine; many records can be found in monastic medicine. Rheumatic and bronchial complaints were treated at that time. Reports of prescriptions for cannabis as an opium substitute have also surfaced.

In the 16th century, herbal books included cannabis. Three hundred years later, in the 19th century, medical applications had migraines, neuralgia, epilepsy-like cramps, and sleep disorders. By 1898, marijuana was America’s most commonly used pain reliever when it was eventually supplanted by aspirin and other synthetic drugs. More than 100 cannabis medicines were commercially available in Europe between the 1850s and 1950s. Due to the development of synthetically produced medicines, difficulties in dosing, and paradoxical modes of action, prescriptions decreased in the 20th century until cannabis as a medicine was banned almost worldwide in the middle of the 20th century.[22]

Cannabis as an intoxicant

The first references to cannabis as a psychoactive substance can be found in Chinese writings in 2737 BC. Although the intoxicating effects were described, the focus was on the medical added value (including rheumatism, gout, and malaria). In India, however, cannabis was used for intoxication.[23]

How cannabis became illegal

The illegalization of cannabis dates back to the first half of the 20th century. During the Opium Conference (organized by the predecessor organization of the UN founded after the First World War) in 1925, cannabis was discussed alongside the debate on opium and cocaine. It was voted that the hemp plant should be included in the list of controlled intoxicants. The reason for the ultimately successful initiative and, thus, stronger control of cannabis was not concerned about health damage but rather economic interests, especially on the part of the German Reich.

The essentially almost universal prohibition of cannabis (with a few exceptions) is closely related to the course of the history of the ban in the United States. Harry Jacob Anslinger, the influential head of FBN (Federal Bureau of Narcotics), known for his racist hate campaigns against minorities, launched a campaign against cannabis in 1931. He is responsible for the signing of the Marihuana Tax Act in 1937 by President Roosevelt. A little later, from 1942 onwards, hemp products for medicinal purposes disappeared from the market except for the synthetically manufactured THC.[24]

Application in medicine

Medicinal use of THC

THC is also found in a wide variety of medicines. In Germany, for example, THC’s effectiveness for treating glaucoma and autoimmune diseases (e.g., multiple sclerosis, Crohn’s disease) is being tested. In America, THC drugs are approved for treating anorexia (anorexia) and cachexia (weight loss) in AIDS.

A study at the Medical University in Hanover concluded that tics in Tourette syndrome sufferers are effectively reduced by treatment with THC.[25]

For the treatment of pain caused by damage or disease of the nervous system, spasms in multiple sclerosis, and to relieve pain, nausea, and vomiting in cancer and AIDS, a medicinal product containing the herbal active ingredients THC and CBD has been developed in Austria, UK and Canada approved. Additional treatment areas of THC are still in clinical testing.[26]

Since March 2017, seriously ill patients in Germany have been allowed to use cannabis as a medicine under certain conditions – for example, to treat pain and nausea caused by cancer and multiple sclerosis. The doctor prescribes the hemp flowers; the health insurance companies bear the costs. However, it is assumed that all other therapies have failed in seriously ill patients.

According to a study, other effects with therapeutic potential are attributed to this active ingredient, regardless of the approval of THC as a drug; these include:

  • Relief of inflammation-related pain
  • Relief of spasticity
  • Relief of nausea and vomiting
  • Reduction of intraocular pressure
  • Facilitation of Sleep
  • Production of the appetizing effect
  • Inhibition of the spread of cancer cells[27]

Medicinal use of CBD

CBD has many beneficial mechanisms of action and exhibits healing properties; therefore, one highly regards the substance in alternative medicine. Experts see CBD “cannabidiol” as the essential component of medical cannabis.

Since you can find cannabinoid receptors in many places in the body, their effects can unfold in several places. Because CBD acts indirectly on the receptors, it affects the nervous and immune systems. They say this substance has nerve-related, psychological problems and autoimmune diseases, showing a positive effect. Since it greatly influences the immune system’s regeneration, there is the assumption that cannabinoids can even reduce cancer cells. Since cannabinoid has antioxidant properties, they can protect human cells and genetic material from negative influences.[28][29][30][31]

Initially, knowledge about the effects of CBD could be obtained from research on animals or studies on isolated cell samples. Although these results are precise, according to critics, they do not have full significance for the effect and possible benefits of CBD in humans.

Based on recent clinical studies on sick or healthy people, one can make the following statements about CBD and its positive influence on some health problems and the effect:

  • possible reduction of autoimmune inflammation in type 1 diabetes[32]
  • can provide support for epilepsy[33][34]
  • can be helpful for anxiety symptoms[35]
  • possible reduction in nicotine dependence[36]
  • can help with sleep disorders[37]
  • can have a positive effect on schizophrenia[38][39]

Cannabis and cancer treatment

The multitude of studies shows that the active cannabinoids in the cannabis plant can help to reduce cancer cells, as they significantly impact the immune system due to their interaction with the human endocannabinoid system. Although not all strains are equally suitable for a successful treatment against cancer, there is a clear connection between the treatment of cannabis and a reduction in cancer cells. Below are some studies that show a helpful form of therapy for cancer patients. Some of these studies examined the effects of the active ingredient THC on various types of cancer; for others, the substance CBD was the focus of the investigations. Both substances you can find in the cannabis plant.

Brain tumor

In the clinical study conducted by the Department of Biochemistry and Molecular Biology at the Complutense University in Madrid and published in the British Journal of Cancer, it was shown that THC (tetrahydrocannabinol), as well as other cannabinoids, can inhibit tumor growth (in two out of nine patients there was a reduction of the tumor cells).[40]

A study published in the Journal of Pharmacology and Experimental Therapeutics established the association between cannabidiol (CBD) and antitumor activity. Administration of the cannabinoid led to a clear drop in the viability of glioma cells (brain tumors of the central nervous system).[41]

Breast cancer

In America, a study was published in the Proceedings of the US National Academy of Sciences (PNAS), showing how cannabinoids can inhibit the growth of breast cancer cells.[42]

The study “Anti-tumor activity of plant cannabinoids with emphasis on the effect of cannabidiol on human breast carcinoma” also shows how effective the two cannabinoids, THC and CBD, can be against breast cancer cell growth; the growth of cancer cells can be drastically reduced. This was published in the Journal of Pharmacology and Experimental Therapeutics.[43]

The study, conducted by the California Pacific Medical Center and published in the US National Library of Medicine, also found that cannabidiol (CBD) reduces breast cancer cell growth and cell spread. In addition, they proved that CBD significantly reduced tumor mass in breast cancer patients.[44]

Lung cancer

The study, conducted in Germany by the Department of General Surgery and published in the US National Library of Medicine, found that cannabinoids (focusing on the cannabinoid CBD) inhibited cancer cell growth and metastasis in lung cancer.[45]

A study conducted by the Harvard Medical Schools Experimental Medicine Department was published in the journal Oncogene showing that THC inhibits the growth factor responsible for cell migration in lung cancer. Further research into THC and its effectiveness in treating lung cancer and metastasis is ongoing based on these findings.[46]

Blood cancer

A study published in the journal Molecular Pharmacology found that cannabinoids cause both growth inhibition and cell death in cellular lymphoma.[47]

According to a study by Virginia Commonwealth University (Department of Pharmacology and Toxicology), cannabinoids can destroy leukemia cells. The US National Library of Medicine published this study.[48]

Important NOTE: The information provided here is as up-to-date and fact-based as possible. However, we would like to point out that this can under no circumstances replace advice and treatment by a doctor.

Weblinks

References

[1] http://www.zeit.de/wissen/gesundheit/2017-06/europaeischer-drogenbericht-drogenkonsum-heroin-opium-cannabis; abgerufen am 18. Dezember 2017

[2] Wolfgang Ferner, Peter Xanke: Alkohol und Drogen im Straßenverkehr – Messverfahren, Bußgeldverfahren, Strafverfahren. Deubner, Recht und Praxis, Köln 2006, ISBN 978-3-88606-633-9, S. 68.

[3] Jörg Fengler (Hrsg.): Handbuch der Suchtbehandlung: Beratung, Therapie, Prävention. ecomed-Storck, Landsberg 2002, ISBN 978-3-609-51980-7, S. 228 

[4] Orrin Devinsky, Maria R. Cilio, Helen Cross, u.a.: Cannabidiol: Pharmacology and potential therapeutic role in epilepsy and other neuropsychiatric disorders. In: Epilepsia. Band 55, Nr. 6, 1. Juni 2014, S. 791–802.

[5] Jonathon Burch: Afghanistan now world’s top cannabis source: U.N

[6] Avoxa. Mediengruppe Deutscher Apotheker GmbH: Pharmazeutische Zeitung online: Cannabis als Medizin: Was kommt auf die Apotheken zu?

[7] Rudolf Hänsel, Ernst Steinegger (Hrsg.): Pharmakognosie – Phytopharmazie. 9., überarb. und akt. Auflage. Springer, Heidelberg 2010, ISBN 978-3-642-00962-4.

[8] Di Marzo V, Stella N, Zimmer A. Endocannabinoid signalling and the deteriorating brain. Nat Rev Neurosci. 2015 Jan;16(1):30-42

[9] Thomas A, Baillie GL, Phillips AM, Razdan RK, Ross RA, Pertwee RG. Cannabidiol displays unexpectedly high potency as an antagonist of CB1 and CB2 receptor agonists in vitro. Br J Pharmacol. 2007 Mar;150(5):613-23

[10] Roger G. Pertwee: Pharmacological and therapeutic targets for Δ9-tetrahydrocannabinol and cannabidiol. In: Euphytica. Band 140, Nr. 1–2, 2004, S. 73–82, doi:10.1007/s10681-004-4756-9.

[11] J. Michael Walker, Susan M. Huang: Cannabinoid analgesia. In: Pharmacology & Therapeutics. Band 95, Nr. 2, 2002, S. 127–135. (S. 128) ”

[12] Cannabis – drugscouts.de. In: drugscouts.de. Abgerufen am 18. Dezember 2017

[13] Wolfgang Ferner, Peter Xanke: Alkohol und Drogen im Straßenverkehr – Messverfahren, Bußgeldverfahren, Strafverfahren. Deubner Verlag, 2006, ISBN 3-88606-633-9, S. 64

[14] Gary L. Wenk: Does Coffee Enhance Marijuana? In: psychologytoday.com. Abgerufen am 18. Dezember 2017

[15] Diana L. Cichewicz: Synergistic interactions between cannabinoid and opioid analgesics. In: Life Sciences. Band 74, Nr. 11, 30. Januar 2004, S. 1317–1324, doi:10.1016/j.lfs.2003.09.038, PMID 14706563.

[16] J. A. McLaren, E. Silins, D. Hutchinson, R. P. Mattick, W. Hall: Assessing evidence for a causal link between cannabis and psychosis: a review of cohort studies. In: The International journal on drug policy. Band 21, Nummer 1, Januar 2010, S. 10–19, doi:10.1016/j.drugpo.2009.09.001. PMID 19783132 (Review).

[17] S. Minozzi, M. Davoli, A. M. Bargagli, L. Amato, S. Vecchi, C. A. Perucci: An overview of systematic reviews on cannabis and psychosis: discussing conflicting results. In: Drug and alcohol review. Band 29, Nummer 3, Mai 2010, S. 304–317, doi:10.1111/j.1465-3362.2009.00132.x. PMID 20565524.

[18] T.H. Moore, S. Zammit, A. Lingford-Hughes, T. R. Barnes, P. B. Jones, M. Burke, G. Lewis: Cannabis use and risk of psychotic or affective mental health outcomes: a systematic review. In: Lancet. Band 370, Nummer 9584, Juli 2007, S. 319–328, doi:10.1016/S0140-6736(07)61162-3.

[19] U. Bonnet, N. Scherbaum: Evidenzbasierte Behandlung der Cannabisabhängigkeit, Deutsches Ärzteblatt, Dezember 2005

[20] http://www.scielo.br/scielo.php?pid=S1516-44462006000200015&script=sci_arttext&tlng=pt

[21] Ethan Russo: Cannabinoids as Therapeutics. Hrsg.: Raphael Mechoulam. Birkhäuser, Basel 2005, ISBN 978-3-7643-7055-8, Kapitel: Cannabis in India: ancient lore and modern medicine, S. 1–22

[22] Cannabis als Medizin. In: cannabislegal.de, Abgerufen am 18. Dezember 2017

[23] https://www.narconon.org/drug-information/marijuana-history.html, Abgerufen am 13. Dezember 2017

[24] https://www.cannabis.info/de/blog/wann-warum-und-wie-marihuana-illegal-wurde, Abgerufen am 19. Dezember 2017

[25] K. R. Müller-Vahl u. a.: Delta 9-tetrahydrocannabinol (THC) is effective in treating tics in Tourette syndrome: a 6-week randomized trial. In: J Clin Psychiatry. 2003.

[26] Sativex® approved in Germany for the treatment of spasticity due to Multiple Sclerosis. GW-Pharmaceuticals.

[27] Roger G. Pertwee: Pharmacological and therapeutic targets for Δ9-tetrahydrocannabinol and cannabidiol. In: Euphytica. Band 140, Nr. 1–2, 2004, S. 73–82, doi:10.1007/s10681-004-4756-9

[28] Lunn CA, Fine JS, Rojas-Triana A, Jackson JV, Fan X, Kung TT, Gonsiorek W, Schwarz MA, Lavey B, Kozlowski JA, Narula SK, Lundell DJ, Hipkin RW, Bober LA. A novel cannabinoid peripheral cannabinoid receptor-selective inverse agonist blocks leukocyte recruitment in vivo. J Pharmacol Exp Ther. 2006 Feb;316(2):780-8

[29] Esposito G, De Filippis D, Maiuri MC, De Stefano D, Carnuccio R, Iuvone T. Cannabidiol inhibits inducible nitric oxide synthase protein expression, and nitric oxide production in beta-amyloid stimulated PC12 neurons through p38 MAP kinase and NF-kappaB involvement. Neurosci Lett. 2006 May 15;399(1-2):91-5

[30] Izzo AA, Borrelli F, Capasso R, Di Marzo V, Mechoulam R. Non-psychotropic plant cannabinoids: new therapeutic opportunities from an ancient herb. Trends Pharmacol Sci. 2009 Oct;30(10):515-27. doi: 10.1016/j.tips.2009.07.006. Epub 2009 Sep 2. Review. Erratum in: Trends Pharmacol Sci. 2009 Dec;30(12):609

[31] Campos AC, Moreira FA, Gomes FV, Del Bel EA, Guimarães. Multiple mechanisms involved in the large-spectrum therapeutic potential of cannabidiol in psychiatric disorders. Philos Trans R Soc Lond B Biol Sci. 2012 Dec 5;367(1607):3364-78

[32] Lehmann C, Fisher NB, Tugwell B, Szczesniak A, Kelly M, Zhou J. Experimental cannabidiol treatment reduces early pancreatic inflammation in type 1 diabetes. Clin Hemorheol Microcirc. 2016;64(4):655-662

[33] Devinsky O, Marsh E, Friedman D, Thiele E, Laux L, Sullivan J, Miller I, Flamini R, Wilfong A, Filloux F, Wong M, Tilton N, Bruno P, Bluvstein J, Hedlund J, Kamens R, Maclean J, Nangia S, Singhal NS, Wilson CA, Patel A, Cilio MR. Cannabidiol in patients with treatment-resistant epilepsy: an open-label interventional trial. Lancet Neurol. 2016 Mar;15(3):270-8

[34] Perez-Reyes M, Wingfield M. Letter: Cannabidiol and electroencephalographic epileptic activity. JAMA. 1974 Dec 23-30;230(12):1635

[35] Das RK, Kamboj SK, Ramadas M, Yogan K, Gupta V, Redman E, Curran HV, Morgan CJ. Cannabidiol enhances consolidation of explicit fear extinction in humans. Psychopharmacology (Berl). 2013 Apr;226(4):781-92

[36] Morgan CJ, Das RK, Joye A, Curran HV, Kamboj SK. Cannabidiol reduces cigarette consumption in tobacco smokers: preliminary findings. Addict Behav. 2013 Sep;38(9):2433-6

[37] Anxiety and Insomnia as Part of Posttraumatic Stress Disorder: A Case Report. Perm J. 2016 Fall;20(4):108-111

[38] Linge R, Jiménez-Sánchez L, Campa L, Pilar-Cuéllar F, Vidal R, Pazos A, Adell A, Díaz Á. Cannabidiol induces rapid-acting antidepressant-like effects and enhances cortical 5-HT/glutamate neurotransmission: role of 5-HT1A receptors. Neuropharmacology. 2016 Apr;103:16-26

[39] Lee JL, Bertoglio LJ, Guimarães FS, Stevenson CW. Cannabidiol regulation of emotion and emotional memory processing: relevance for treating anxiety-related and substance abuse disorders. Br J Pharmacol. 2017 Mar 7

[40] M Guzmán, M J Duarte, C Blázquez, J Ravina, M C Rosa, I Galve-Roperh, C Sánchez, G Velasco & L González-Feria. A pilot clinical study of Δ9-tetrahydrocannabinol in patients with recurrent glioblastoma multiforme. British Journal of Cancer (2006) 95, 197–203

[41]Paola Massi, Angelo Vaccani, Stefania Ceruti, Arianna Colombo, Maria P. Abbracchio and Daniela Parolaro, Antitumor Effects of Cannabidiol, a Nonpsychoactive Cannabinoid, on Human Glioma Cell Lines. Journal of Pharmacology and Experimental Therapeutics March 2004, 308 (3) 838-845.

[42] L. de Petrocellis, D. Melck, ua.The endogenous cannabinoid anandamide inhibits human breast
cancer cell proliferation, Proc. Natl. Acad. Sci. USA Vol. 95, pp. 8375–8380, July 1998

[43] Alessia Ligresti, Aniello Schiano Moriello, Katarzyna Starowicz, Isabel Matias, Simona Pisanti, Luciano De Petrocellis, Chiara Laezza, Giuseppe Portella, Maurizio Bifulco and Vincenzo Di Marzo. Anti-tumor activity of plant cannabinoids with emphasis on the effect of cannabidiol on human breast carcinoma. Journal of Pharmacology and Experimental Therapeutics May 25, 2006

[44] McAllister SD1, Murase R, Christian RT, Lau D, Zielinski AJ, Allison J, Almanza C, Pakdel A, Lee J, Limbad C, Liu Y, Debs RJ, Moore DH, Desprez PY. Pathways mediating the effects of cannabidiol on the reduction of breast cancer cell proliferation, invasion, and metastasis. 2011 Aug;129(1):37-47. doi: 10.1007/s10549-010-1177-4. Epub 2010 Sep 22.

[45] Ramer R1, Bublitz K, Freimuth N, Merkord J, Rohde H, Haustein M, Borchert P, Schmuhl E, Linnebacher M, Hinz B. Cannabidiol inhibits lung cancer cell invasion and metastasis via intercellular adhesion molecule-1. 2012 Apr;26(4):1535-48. doi.

[46] A Preet, R K Ganju & J E Groopman, Δ9-Tetrahydrocannabinol inhibits epithelial growth factor-induced lung cancer cell migration in vitro as well as its growth and metastasis in vivo, 27, 339–346 (10 January 2008)

[47] Kristin Gustafsson, Birger Christensson, Birgitta Sander and Jenny Flygare, Cannabinoid Receptor-Mediated Apoptosis Induced by R(+)-Methanandamide and Win55,212-2 Is Associated with Ceramide Accumulation and p38 Activation in Mantle. Molecular Pharmacology November 2006

[48] Jia W1, Hegde VL, Singh NP, Sisco D, Grant S, Nagarkatti M, Nagarkatti PS., Delta9-tetrahydrocannabinol-induced apoptosis in Jurkat leukemia T cells is regulated by translocation of Bad to mitochondria. 2006 Aug;4(8):549-62.